xref: /sqlite-3.40.0/src/insert.c (revision 1e2896ec)
1 /*
2 ** 2001 September 15
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 *************************************************************************
12 ** This file contains C code routines that are called by the parser
13 ** to handle INSERT statements in SQLite.
14 */
15 #include "sqliteInt.h"
16 
17 /*
18 ** Generate code that will
19 **
20 **   (1) acquire a lock for table pTab then
21 **   (2) open pTab as cursor iCur.
22 **
23 ** If pTab is a WITHOUT ROWID table, then it is the PRIMARY KEY index
24 ** for that table that is actually opened.
25 */
26 void sqlite3OpenTable(
27   Parse *pParse,  /* Generate code into this VDBE */
28   int iCur,       /* The cursor number of the table */
29   int iDb,        /* The database index in sqlite3.aDb[] */
30   Table *pTab,    /* The table to be opened */
31   int opcode      /* OP_OpenRead or OP_OpenWrite */
32 ){
33   Vdbe *v;
34   assert( !IsVirtual(pTab) );
35   assert( pParse->pVdbe!=0 );
36   v = pParse->pVdbe;
37   assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
38   sqlite3TableLock(pParse, iDb, pTab->tnum,
39                    (opcode==OP_OpenWrite)?1:0, pTab->zName);
40   if( HasRowid(pTab) ){
41     sqlite3VdbeAddOp4Int(v, opcode, iCur, pTab->tnum, iDb, pTab->nNVCol);
42     VdbeComment((v, "%s", pTab->zName));
43   }else{
44     Index *pPk = sqlite3PrimaryKeyIndex(pTab);
45     assert( pPk!=0 );
46     assert( pPk->tnum==pTab->tnum );
47     sqlite3VdbeAddOp3(v, opcode, iCur, pPk->tnum, iDb);
48     sqlite3VdbeSetP4KeyInfo(pParse, pPk);
49     VdbeComment((v, "%s", pTab->zName));
50   }
51 }
52 
53 /*
54 ** Return a pointer to the column affinity string associated with index
55 ** pIdx. A column affinity string has one character for each column in
56 ** the table, according to the affinity of the column:
57 **
58 **  Character      Column affinity
59 **  ------------------------------
60 **  'A'            BLOB
61 **  'B'            TEXT
62 **  'C'            NUMERIC
63 **  'D'            INTEGER
64 **  'F'            REAL
65 **
66 ** An extra 'D' is appended to the end of the string to cover the
67 ** rowid that appears as the last column in every index.
68 **
69 ** Memory for the buffer containing the column index affinity string
70 ** is managed along with the rest of the Index structure. It will be
71 ** released when sqlite3DeleteIndex() is called.
72 */
73 const char *sqlite3IndexAffinityStr(sqlite3 *db, Index *pIdx){
74   if( !pIdx->zColAff ){
75     /* The first time a column affinity string for a particular index is
76     ** required, it is allocated and populated here. It is then stored as
77     ** a member of the Index structure for subsequent use.
78     **
79     ** The column affinity string will eventually be deleted by
80     ** sqliteDeleteIndex() when the Index structure itself is cleaned
81     ** up.
82     */
83     int n;
84     Table *pTab = pIdx->pTable;
85     pIdx->zColAff = (char *)sqlite3DbMallocRaw(0, pIdx->nColumn+1);
86     if( !pIdx->zColAff ){
87       sqlite3OomFault(db);
88       return 0;
89     }
90     for(n=0; n<pIdx->nColumn; n++){
91       i16 x = pIdx->aiColumn[n];
92       char aff;
93       if( x>=0 ){
94         aff = pTab->aCol[x].affinity;
95       }else if( x==XN_ROWID ){
96         aff = SQLITE_AFF_INTEGER;
97       }else{
98         assert( x==XN_EXPR );
99         assert( pIdx->aColExpr!=0 );
100         aff = sqlite3ExprAffinity(pIdx->aColExpr->a[n].pExpr);
101       }
102       if( aff<SQLITE_AFF_BLOB ) aff = SQLITE_AFF_BLOB;
103       if( aff>SQLITE_AFF_NUMERIC) aff = SQLITE_AFF_NUMERIC;
104       pIdx->zColAff[n] = aff;
105     }
106     pIdx->zColAff[n] = 0;
107   }
108 
109   return pIdx->zColAff;
110 }
111 
112 /*
113 ** Compute the affinity string for table pTab, if it has not already been
114 ** computed.  As an optimization, omit trailing SQLITE_AFF_BLOB affinities.
115 **
116 ** If the affinity exists (if it is no entirely SQLITE_AFF_BLOB values) and
117 ** if iReg>0 then code an OP_Affinity opcode that will set the affinities
118 ** for register iReg and following.  Or if affinities exists and iReg==0,
119 ** then just set the P4 operand of the previous opcode (which should  be
120 ** an OP_MakeRecord) to the affinity string.
121 **
122 ** A column affinity string has one character per column:
123 **
124 **  Character      Column affinity
125 **  ------------------------------
126 **  'A'            BLOB
127 **  'B'            TEXT
128 **  'C'            NUMERIC
129 **  'D'            INTEGER
130 **  'E'            REAL
131 */
132 void sqlite3TableAffinity(Vdbe *v, Table *pTab, int iReg){
133   int i, j;
134   char *zColAff = pTab->zColAff;
135   if( zColAff==0 ){
136     sqlite3 *db = sqlite3VdbeDb(v);
137     zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1);
138     if( !zColAff ){
139       sqlite3OomFault(db);
140       return;
141     }
142 
143     for(i=j=0; i<pTab->nCol; i++){
144       assert( pTab->aCol[i].affinity!=0 );
145       if( (pTab->aCol[i].colFlags & COLFLAG_VIRTUAL)==0 ){
146         zColAff[j++] = pTab->aCol[i].affinity;
147       }
148     }
149     do{
150       zColAff[j--] = 0;
151     }while( j>=0 && zColAff[j]<=SQLITE_AFF_BLOB );
152     pTab->zColAff = zColAff;
153   }
154   assert( zColAff!=0 );
155   i = sqlite3Strlen30NN(zColAff);
156   if( i ){
157     if( iReg ){
158       sqlite3VdbeAddOp4(v, OP_Affinity, iReg, i, 0, zColAff, i);
159     }else{
160       sqlite3VdbeChangeP4(v, -1, zColAff, i);
161     }
162   }
163 }
164 
165 /*
166 ** Return non-zero if the table pTab in database iDb or any of its indices
167 ** have been opened at any point in the VDBE program. This is used to see if
168 ** a statement of the form  "INSERT INTO <iDb, pTab> SELECT ..." can
169 ** run without using a temporary table for the results of the SELECT.
170 */
171 static int readsTable(Parse *p, int iDb, Table *pTab){
172   Vdbe *v = sqlite3GetVdbe(p);
173   int i;
174   int iEnd = sqlite3VdbeCurrentAddr(v);
175 #ifndef SQLITE_OMIT_VIRTUALTABLE
176   VTable *pVTab = IsVirtual(pTab) ? sqlite3GetVTable(p->db, pTab) : 0;
177 #endif
178 
179   for(i=1; i<iEnd; i++){
180     VdbeOp *pOp = sqlite3VdbeGetOp(v, i);
181     assert( pOp!=0 );
182     if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){
183       Index *pIndex;
184       Pgno tnum = pOp->p2;
185       if( tnum==pTab->tnum ){
186         return 1;
187       }
188       for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){
189         if( tnum==pIndex->tnum ){
190           return 1;
191         }
192       }
193     }
194 #ifndef SQLITE_OMIT_VIRTUALTABLE
195     if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pVTab ){
196       assert( pOp->p4.pVtab!=0 );
197       assert( pOp->p4type==P4_VTAB );
198       return 1;
199     }
200 #endif
201   }
202   return 0;
203 }
204 
205 /* This walker callback will compute the union of colFlags flags for all
206 ** referenced columns in a CHECK constraint or generated column expression.
207 */
208 static int exprColumnFlagUnion(Walker *pWalker, Expr *pExpr){
209   if( pExpr->op==TK_COLUMN && pExpr->iColumn>=0 ){
210     assert( pExpr->iColumn < pWalker->u.pTab->nCol );
211     pWalker->eCode |= pWalker->u.pTab->aCol[pExpr->iColumn].colFlags;
212   }
213   return WRC_Continue;
214 }
215 
216 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
217 /*
218 ** All regular columns for table pTab have been puts into registers
219 ** starting with iRegStore.  The registers that correspond to STORED
220 ** or VIRTUAL columns have not yet been initialized.  This routine goes
221 ** back and computes the values for those columns based on the previously
222 ** computed normal columns.
223 */
224 void sqlite3ComputeGeneratedColumns(
225   Parse *pParse,    /* Parsing context */
226   int iRegStore,    /* Register holding the first column */
227   Table *pTab       /* The table */
228 ){
229   int i;
230   Walker w;
231   Column *pRedo;
232   int eProgress;
233   VdbeOp *pOp;
234 
235   assert( pTab->tabFlags & TF_HasGenerated );
236   testcase( pTab->tabFlags & TF_HasVirtual );
237   testcase( pTab->tabFlags & TF_HasStored );
238 
239   /* Before computing generated columns, first go through and make sure
240   ** that appropriate affinity has been applied to the regular columns
241   */
242   sqlite3TableAffinity(pParse->pVdbe, pTab, iRegStore);
243   if( (pTab->tabFlags & TF_HasStored)!=0
244    && (pOp = sqlite3VdbeGetOp(pParse->pVdbe,-1))->opcode==OP_Affinity
245   ){
246     /* Change the OP_Affinity argument to '@' (NONE) for all stored
247     ** columns.  '@' is the no-op affinity and those columns have not
248     ** yet been computed. */
249     int ii, jj;
250     char *zP4 = pOp->p4.z;
251     assert( zP4!=0 );
252     assert( pOp->p4type==P4_DYNAMIC );
253     for(ii=jj=0; zP4[jj]; ii++){
254       if( pTab->aCol[ii].colFlags & COLFLAG_VIRTUAL ){
255         continue;
256       }
257       if( pTab->aCol[ii].colFlags & COLFLAG_STORED ){
258         zP4[jj] = SQLITE_AFF_NONE;
259       }
260       jj++;
261     }
262   }
263 
264   /* Because there can be multiple generated columns that refer to one another,
265   ** this is a two-pass algorithm.  On the first pass, mark all generated
266   ** columns as "not available".
267   */
268   for(i=0; i<pTab->nCol; i++){
269     if( pTab->aCol[i].colFlags & COLFLAG_GENERATED ){
270       testcase( pTab->aCol[i].colFlags & COLFLAG_VIRTUAL );
271       testcase( pTab->aCol[i].colFlags & COLFLAG_STORED );
272       pTab->aCol[i].colFlags |= COLFLAG_NOTAVAIL;
273     }
274   }
275 
276   w.u.pTab = pTab;
277   w.xExprCallback = exprColumnFlagUnion;
278   w.xSelectCallback = 0;
279   w.xSelectCallback2 = 0;
280 
281   /* On the second pass, compute the value of each NOT-AVAILABLE column.
282   ** Companion code in the TK_COLUMN case of sqlite3ExprCodeTarget() will
283   ** compute dependencies and mark remove the COLSPAN_NOTAVAIL mark, as
284   ** they are needed.
285   */
286   pParse->iSelfTab = -iRegStore;
287   do{
288     eProgress = 0;
289     pRedo = 0;
290     for(i=0; i<pTab->nCol; i++){
291       Column *pCol = pTab->aCol + i;
292       if( (pCol->colFlags & COLFLAG_NOTAVAIL)!=0 ){
293         int x;
294         pCol->colFlags |= COLFLAG_BUSY;
295         w.eCode = 0;
296         sqlite3WalkExpr(&w, pCol->pDflt);
297         pCol->colFlags &= ~COLFLAG_BUSY;
298         if( w.eCode & COLFLAG_NOTAVAIL ){
299           pRedo = pCol;
300           continue;
301         }
302         eProgress = 1;
303         assert( pCol->colFlags & COLFLAG_GENERATED );
304         x = sqlite3TableColumnToStorage(pTab, i) + iRegStore;
305         sqlite3ExprCodeGeneratedColumn(pParse, pCol, x);
306         pCol->colFlags &= ~COLFLAG_NOTAVAIL;
307       }
308     }
309   }while( pRedo && eProgress );
310   if( pRedo ){
311     sqlite3ErrorMsg(pParse, "generated column loop on \"%s\"", pRedo->zName);
312   }
313   pParse->iSelfTab = 0;
314 }
315 #endif /* SQLITE_OMIT_GENERATED_COLUMNS */
316 
317 
318 #ifndef SQLITE_OMIT_AUTOINCREMENT
319 /*
320 ** Locate or create an AutoincInfo structure associated with table pTab
321 ** which is in database iDb.  Return the register number for the register
322 ** that holds the maximum rowid.  Return zero if pTab is not an AUTOINCREMENT
323 ** table.  (Also return zero when doing a VACUUM since we do not want to
324 ** update the AUTOINCREMENT counters during a VACUUM.)
325 **
326 ** There is at most one AutoincInfo structure per table even if the
327 ** same table is autoincremented multiple times due to inserts within
328 ** triggers.  A new AutoincInfo structure is created if this is the
329 ** first use of table pTab.  On 2nd and subsequent uses, the original
330 ** AutoincInfo structure is used.
331 **
332 ** Four consecutive registers are allocated:
333 **
334 **   (1)  The name of the pTab table.
335 **   (2)  The maximum ROWID of pTab.
336 **   (3)  The rowid in sqlite_sequence of pTab
337 **   (4)  The original value of the max ROWID in pTab, or NULL if none
338 **
339 ** The 2nd register is the one that is returned.  That is all the
340 ** insert routine needs to know about.
341 */
342 static int autoIncBegin(
343   Parse *pParse,      /* Parsing context */
344   int iDb,            /* Index of the database holding pTab */
345   Table *pTab         /* The table we are writing to */
346 ){
347   int memId = 0;      /* Register holding maximum rowid */
348   assert( pParse->db->aDb[iDb].pSchema!=0 );
349   if( (pTab->tabFlags & TF_Autoincrement)!=0
350    && (pParse->db->mDbFlags & DBFLAG_Vacuum)==0
351   ){
352     Parse *pToplevel = sqlite3ParseToplevel(pParse);
353     AutoincInfo *pInfo;
354     Table *pSeqTab = pParse->db->aDb[iDb].pSchema->pSeqTab;
355 
356     /* Verify that the sqlite_sequence table exists and is an ordinary
357     ** rowid table with exactly two columns.
358     ** Ticket d8dc2b3a58cd5dc2918a1d4acb 2018-05-23 */
359     if( pSeqTab==0
360      || !HasRowid(pSeqTab)
361      || IsVirtual(pSeqTab)
362      || pSeqTab->nCol!=2
363     ){
364       pParse->nErr++;
365       pParse->rc = SQLITE_CORRUPT_SEQUENCE;
366       return 0;
367     }
368 
369     pInfo = pToplevel->pAinc;
370     while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; }
371     if( pInfo==0 ){
372       pInfo = sqlite3DbMallocRawNN(pParse->db, sizeof(*pInfo));
373       sqlite3ParserAddCleanup(pToplevel, sqlite3DbFree, pInfo);
374       testcase( pParse->earlyCleanup );
375       if( pParse->db->mallocFailed ) return 0;
376       pInfo->pNext = pToplevel->pAinc;
377       pToplevel->pAinc = pInfo;
378       pInfo->pTab = pTab;
379       pInfo->iDb = iDb;
380       pToplevel->nMem++;                  /* Register to hold name of table */
381       pInfo->regCtr = ++pToplevel->nMem;  /* Max rowid register */
382       pToplevel->nMem +=2;       /* Rowid in sqlite_sequence + orig max val */
383     }
384     memId = pInfo->regCtr;
385   }
386   return memId;
387 }
388 
389 /*
390 ** This routine generates code that will initialize all of the
391 ** register used by the autoincrement tracker.
392 */
393 void sqlite3AutoincrementBegin(Parse *pParse){
394   AutoincInfo *p;            /* Information about an AUTOINCREMENT */
395   sqlite3 *db = pParse->db;  /* The database connection */
396   Db *pDb;                   /* Database only autoinc table */
397   int memId;                 /* Register holding max rowid */
398   Vdbe *v = pParse->pVdbe;   /* VDBE under construction */
399 
400   /* This routine is never called during trigger-generation.  It is
401   ** only called from the top-level */
402   assert( pParse->pTriggerTab==0 );
403   assert( sqlite3IsToplevel(pParse) );
404 
405   assert( v );   /* We failed long ago if this is not so */
406   for(p = pParse->pAinc; p; p = p->pNext){
407     static const int iLn = VDBE_OFFSET_LINENO(2);
408     static const VdbeOpList autoInc[] = {
409       /* 0  */ {OP_Null,    0,  0, 0},
410       /* 1  */ {OP_Rewind,  0, 10, 0},
411       /* 2  */ {OP_Column,  0,  0, 0},
412       /* 3  */ {OP_Ne,      0,  9, 0},
413       /* 4  */ {OP_Rowid,   0,  0, 0},
414       /* 5  */ {OP_Column,  0,  1, 0},
415       /* 6  */ {OP_AddImm,  0,  0, 0},
416       /* 7  */ {OP_Copy,    0,  0, 0},
417       /* 8  */ {OP_Goto,    0, 11, 0},
418       /* 9  */ {OP_Next,    0,  2, 0},
419       /* 10 */ {OP_Integer, 0,  0, 0},
420       /* 11 */ {OP_Close,   0,  0, 0}
421     };
422     VdbeOp *aOp;
423     pDb = &db->aDb[p->iDb];
424     memId = p->regCtr;
425     assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) );
426     sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
427     sqlite3VdbeLoadString(v, memId-1, p->pTab->zName);
428     aOp = sqlite3VdbeAddOpList(v, ArraySize(autoInc), autoInc, iLn);
429     if( aOp==0 ) break;
430     aOp[0].p2 = memId;
431     aOp[0].p3 = memId+2;
432     aOp[2].p3 = memId;
433     aOp[3].p1 = memId-1;
434     aOp[3].p3 = memId;
435     aOp[3].p5 = SQLITE_JUMPIFNULL;
436     aOp[4].p2 = memId+1;
437     aOp[5].p3 = memId;
438     aOp[6].p1 = memId;
439     aOp[7].p2 = memId+2;
440     aOp[7].p1 = memId;
441     aOp[10].p2 = memId;
442     if( pParse->nTab==0 ) pParse->nTab = 1;
443   }
444 }
445 
446 /*
447 ** Update the maximum rowid for an autoincrement calculation.
448 **
449 ** This routine should be called when the regRowid register holds a
450 ** new rowid that is about to be inserted.  If that new rowid is
451 ** larger than the maximum rowid in the memId memory cell, then the
452 ** memory cell is updated.
453 */
454 static void autoIncStep(Parse *pParse, int memId, int regRowid){
455   if( memId>0 ){
456     sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid);
457   }
458 }
459 
460 /*
461 ** This routine generates the code needed to write autoincrement
462 ** maximum rowid values back into the sqlite_sequence register.
463 ** Every statement that might do an INSERT into an autoincrement
464 ** table (either directly or through triggers) needs to call this
465 ** routine just before the "exit" code.
466 */
467 static SQLITE_NOINLINE void autoIncrementEnd(Parse *pParse){
468   AutoincInfo *p;
469   Vdbe *v = pParse->pVdbe;
470   sqlite3 *db = pParse->db;
471 
472   assert( v );
473   for(p = pParse->pAinc; p; p = p->pNext){
474     static const int iLn = VDBE_OFFSET_LINENO(2);
475     static const VdbeOpList autoIncEnd[] = {
476       /* 0 */ {OP_NotNull,     0, 2, 0},
477       /* 1 */ {OP_NewRowid,    0, 0, 0},
478       /* 2 */ {OP_MakeRecord,  0, 2, 0},
479       /* 3 */ {OP_Insert,      0, 0, 0},
480       /* 4 */ {OP_Close,       0, 0, 0}
481     };
482     VdbeOp *aOp;
483     Db *pDb = &db->aDb[p->iDb];
484     int iRec;
485     int memId = p->regCtr;
486 
487     iRec = sqlite3GetTempReg(pParse);
488     assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) );
489     sqlite3VdbeAddOp3(v, OP_Le, memId+2, sqlite3VdbeCurrentAddr(v)+7, memId);
490     VdbeCoverage(v);
491     sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
492     aOp = sqlite3VdbeAddOpList(v, ArraySize(autoIncEnd), autoIncEnd, iLn);
493     if( aOp==0 ) break;
494     aOp[0].p1 = memId+1;
495     aOp[1].p2 = memId+1;
496     aOp[2].p1 = memId-1;
497     aOp[2].p3 = iRec;
498     aOp[3].p2 = iRec;
499     aOp[3].p3 = memId+1;
500     aOp[3].p5 = OPFLAG_APPEND;
501     sqlite3ReleaseTempReg(pParse, iRec);
502   }
503 }
504 void sqlite3AutoincrementEnd(Parse *pParse){
505   if( pParse->pAinc ) autoIncrementEnd(pParse);
506 }
507 #else
508 /*
509 ** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines
510 ** above are all no-ops
511 */
512 # define autoIncBegin(A,B,C) (0)
513 # define autoIncStep(A,B,C)
514 #endif /* SQLITE_OMIT_AUTOINCREMENT */
515 
516 
517 /* Forward declaration */
518 static int xferOptimization(
519   Parse *pParse,        /* Parser context */
520   Table *pDest,         /* The table we are inserting into */
521   Select *pSelect,      /* A SELECT statement to use as the data source */
522   int onError,          /* How to handle constraint errors */
523   int iDbDest           /* The database of pDest */
524 );
525 
526 /*
527 ** This routine is called to handle SQL of the following forms:
528 **
529 **    insert into TABLE (IDLIST) values(EXPRLIST),(EXPRLIST),...
530 **    insert into TABLE (IDLIST) select
531 **    insert into TABLE (IDLIST) default values
532 **
533 ** The IDLIST following the table name is always optional.  If omitted,
534 ** then a list of all (non-hidden) columns for the table is substituted.
535 ** The IDLIST appears in the pColumn parameter.  pColumn is NULL if IDLIST
536 ** is omitted.
537 **
538 ** For the pSelect parameter holds the values to be inserted for the
539 ** first two forms shown above.  A VALUES clause is really just short-hand
540 ** for a SELECT statement that omits the FROM clause and everything else
541 ** that follows.  If the pSelect parameter is NULL, that means that the
542 ** DEFAULT VALUES form of the INSERT statement is intended.
543 **
544 ** The code generated follows one of four templates.  For a simple
545 ** insert with data coming from a single-row VALUES clause, the code executes
546 ** once straight down through.  Pseudo-code follows (we call this
547 ** the "1st template"):
548 **
549 **         open write cursor to <table> and its indices
550 **         put VALUES clause expressions into registers
551 **         write the resulting record into <table>
552 **         cleanup
553 **
554 ** The three remaining templates assume the statement is of the form
555 **
556 **   INSERT INTO <table> SELECT ...
557 **
558 ** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" -
559 ** in other words if the SELECT pulls all columns from a single table
560 ** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and
561 ** if <table2> and <table1> are distinct tables but have identical
562 ** schemas, including all the same indices, then a special optimization
563 ** is invoked that copies raw records from <table2> over to <table1>.
564 ** See the xferOptimization() function for the implementation of this
565 ** template.  This is the 2nd template.
566 **
567 **         open a write cursor to <table>
568 **         open read cursor on <table2>
569 **         transfer all records in <table2> over to <table>
570 **         close cursors
571 **         foreach index on <table>
572 **           open a write cursor on the <table> index
573 **           open a read cursor on the corresponding <table2> index
574 **           transfer all records from the read to the write cursors
575 **           close cursors
576 **         end foreach
577 **
578 ** The 3rd template is for when the second template does not apply
579 ** and the SELECT clause does not read from <table> at any time.
580 ** The generated code follows this template:
581 **
582 **         X <- A
583 **         goto B
584 **      A: setup for the SELECT
585 **         loop over the rows in the SELECT
586 **           load values into registers R..R+n
587 **           yield X
588 **         end loop
589 **         cleanup after the SELECT
590 **         end-coroutine X
591 **      B: open write cursor to <table> and its indices
592 **      C: yield X, at EOF goto D
593 **         insert the select result into <table> from R..R+n
594 **         goto C
595 **      D: cleanup
596 **
597 ** The 4th template is used if the insert statement takes its
598 ** values from a SELECT but the data is being inserted into a table
599 ** that is also read as part of the SELECT.  In the third form,
600 ** we have to use an intermediate table to store the results of
601 ** the select.  The template is like this:
602 **
603 **         X <- A
604 **         goto B
605 **      A: setup for the SELECT
606 **         loop over the tables in the SELECT
607 **           load value into register R..R+n
608 **           yield X
609 **         end loop
610 **         cleanup after the SELECT
611 **         end co-routine R
612 **      B: open temp table
613 **      L: yield X, at EOF goto M
614 **         insert row from R..R+n into temp table
615 **         goto L
616 **      M: open write cursor to <table> and its indices
617 **         rewind temp table
618 **      C: loop over rows of intermediate table
619 **           transfer values form intermediate table into <table>
620 **         end loop
621 **      D: cleanup
622 */
623 void sqlite3Insert(
624   Parse *pParse,        /* Parser context */
625   SrcList *pTabList,    /* Name of table into which we are inserting */
626   Select *pSelect,      /* A SELECT statement to use as the data source */
627   IdList *pColumn,      /* Column names corresponding to IDLIST, or NULL. */
628   int onError,          /* How to handle constraint errors */
629   Upsert *pUpsert       /* ON CONFLICT clauses for upsert, or NULL */
630 ){
631   sqlite3 *db;          /* The main database structure */
632   Table *pTab;          /* The table to insert into.  aka TABLE */
633   int i, j;             /* Loop counters */
634   Vdbe *v;              /* Generate code into this virtual machine */
635   Index *pIdx;          /* For looping over indices of the table */
636   int nColumn;          /* Number of columns in the data */
637   int nHidden = 0;      /* Number of hidden columns if TABLE is virtual */
638   int iDataCur = 0;     /* VDBE cursor that is the main data repository */
639   int iIdxCur = 0;      /* First index cursor */
640   int ipkColumn = -1;   /* Column that is the INTEGER PRIMARY KEY */
641   int endOfLoop;        /* Label for the end of the insertion loop */
642   int srcTab = 0;       /* Data comes from this temporary cursor if >=0 */
643   int addrInsTop = 0;   /* Jump to label "D" */
644   int addrCont = 0;     /* Top of insert loop. Label "C" in templates 3 and 4 */
645   SelectDest dest;      /* Destination for SELECT on rhs of INSERT */
646   int iDb;              /* Index of database holding TABLE */
647   u8 useTempTable = 0;  /* Store SELECT results in intermediate table */
648   u8 appendFlag = 0;    /* True if the insert is likely to be an append */
649   u8 withoutRowid;      /* 0 for normal table.  1 for WITHOUT ROWID table */
650   u8 bIdListInOrder;    /* True if IDLIST is in table order */
651   ExprList *pList = 0;  /* List of VALUES() to be inserted  */
652   int iRegStore;        /* Register in which to store next column */
653 
654   /* Register allocations */
655   int regFromSelect = 0;/* Base register for data coming from SELECT */
656   int regAutoinc = 0;   /* Register holding the AUTOINCREMENT counter */
657   int regRowCount = 0;  /* Memory cell used for the row counter */
658   int regIns;           /* Block of regs holding rowid+data being inserted */
659   int regRowid;         /* registers holding insert rowid */
660   int regData;          /* register holding first column to insert */
661   int *aRegIdx = 0;     /* One register allocated to each index */
662 
663 #ifndef SQLITE_OMIT_TRIGGER
664   int isView;                 /* True if attempting to insert into a view */
665   Trigger *pTrigger;          /* List of triggers on pTab, if required */
666   int tmask;                  /* Mask of trigger times */
667 #endif
668 
669   db = pParse->db;
670   if( pParse->nErr || db->mallocFailed ){
671     goto insert_cleanup;
672   }
673   dest.iSDParm = 0;  /* Suppress a harmless compiler warning */
674 
675   /* If the Select object is really just a simple VALUES() list with a
676   ** single row (the common case) then keep that one row of values
677   ** and discard the other (unused) parts of the pSelect object
678   */
679   if( pSelect && (pSelect->selFlags & SF_Values)!=0 && pSelect->pPrior==0 ){
680     pList = pSelect->pEList;
681     pSelect->pEList = 0;
682     sqlite3SelectDelete(db, pSelect);
683     pSelect = 0;
684   }
685 
686   /* Locate the table into which we will be inserting new information.
687   */
688   assert( pTabList->nSrc==1 );
689   pTab = sqlite3SrcListLookup(pParse, pTabList);
690   if( pTab==0 ){
691     goto insert_cleanup;
692   }
693   iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
694   assert( iDb<db->nDb );
695   if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0,
696                        db->aDb[iDb].zDbSName) ){
697     goto insert_cleanup;
698   }
699   withoutRowid = !HasRowid(pTab);
700 
701   /* Figure out if we have any triggers and if the table being
702   ** inserted into is a view
703   */
704 #ifndef SQLITE_OMIT_TRIGGER
705   pTrigger = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask);
706   isView = pTab->pSelect!=0;
707 #else
708 # define pTrigger 0
709 # define tmask 0
710 # define isView 0
711 #endif
712 #ifdef SQLITE_OMIT_VIEW
713 # undef isView
714 # define isView 0
715 #endif
716   assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) );
717 
718   /* If pTab is really a view, make sure it has been initialized.
719   ** ViewGetColumnNames() is a no-op if pTab is not a view.
720   */
721   if( sqlite3ViewGetColumnNames(pParse, pTab) ){
722     goto insert_cleanup;
723   }
724 
725   /* Cannot insert into a read-only table.
726   */
727   if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
728     goto insert_cleanup;
729   }
730 
731   /* Allocate a VDBE
732   */
733   v = sqlite3GetVdbe(pParse);
734   if( v==0 ) goto insert_cleanup;
735   if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
736   sqlite3BeginWriteOperation(pParse, pSelect || pTrigger, iDb);
737 
738 #ifndef SQLITE_OMIT_XFER_OPT
739   /* If the statement is of the form
740   **
741   **       INSERT INTO <table1> SELECT * FROM <table2>;
742   **
743   ** Then special optimizations can be applied that make the transfer
744   ** very fast and which reduce fragmentation of indices.
745   **
746   ** This is the 2nd template.
747   */
748   if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
749     assert( !pTrigger );
750     assert( pList==0 );
751     goto insert_end;
752   }
753 #endif /* SQLITE_OMIT_XFER_OPT */
754 
755   /* If this is an AUTOINCREMENT table, look up the sequence number in the
756   ** sqlite_sequence table and store it in memory cell regAutoinc.
757   */
758   regAutoinc = autoIncBegin(pParse, iDb, pTab);
759 
760   /* Allocate a block registers to hold the rowid and the values
761   ** for all columns of the new row.
762   */
763   regRowid = regIns = pParse->nMem+1;
764   pParse->nMem += pTab->nCol + 1;
765   if( IsVirtual(pTab) ){
766     regRowid++;
767     pParse->nMem++;
768   }
769   regData = regRowid+1;
770 
771   /* If the INSERT statement included an IDLIST term, then make sure
772   ** all elements of the IDLIST really are columns of the table and
773   ** remember the column indices.
774   **
775   ** If the table has an INTEGER PRIMARY KEY column and that column
776   ** is named in the IDLIST, then record in the ipkColumn variable
777   ** the index into IDLIST of the primary key column.  ipkColumn is
778   ** the index of the primary key as it appears in IDLIST, not as
779   ** is appears in the original table.  (The index of the INTEGER
780   ** PRIMARY KEY in the original table is pTab->iPKey.)  After this
781   ** loop, if ipkColumn==(-1), that means that integer primary key
782   ** is unspecified, and hence the table is either WITHOUT ROWID or
783   ** it will automatically generated an integer primary key.
784   **
785   ** bIdListInOrder is true if the columns in IDLIST are in storage
786   ** order.  This enables an optimization that avoids shuffling the
787   ** columns into storage order.  False negatives are harmless,
788   ** but false positives will cause database corruption.
789   */
790   bIdListInOrder = (pTab->tabFlags & (TF_OOOHidden|TF_HasStored))==0;
791   if( pColumn ){
792     for(i=0; i<pColumn->nId; i++){
793       pColumn->a[i].idx = -1;
794     }
795     for(i=0; i<pColumn->nId; i++){
796       for(j=0; j<pTab->nCol; j++){
797         if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
798           pColumn->a[i].idx = j;
799           if( i!=j ) bIdListInOrder = 0;
800           if( j==pTab->iPKey ){
801             ipkColumn = i;  assert( !withoutRowid );
802           }
803 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
804           if( pTab->aCol[j].colFlags & (COLFLAG_STORED|COLFLAG_VIRTUAL) ){
805             sqlite3ErrorMsg(pParse,
806                "cannot INSERT into generated column \"%s\"",
807                pTab->aCol[j].zName);
808             goto insert_cleanup;
809           }
810 #endif
811           break;
812         }
813       }
814       if( j>=pTab->nCol ){
815         if( sqlite3IsRowid(pColumn->a[i].zName) && !withoutRowid ){
816           ipkColumn = i;
817           bIdListInOrder = 0;
818         }else{
819           sqlite3ErrorMsg(pParse, "table %S has no column named %s",
820               pTabList, 0, pColumn->a[i].zName);
821           pParse->checkSchema = 1;
822           goto insert_cleanup;
823         }
824       }
825     }
826   }
827 
828   /* Figure out how many columns of data are supplied.  If the data
829   ** is coming from a SELECT statement, then generate a co-routine that
830   ** produces a single row of the SELECT on each invocation.  The
831   ** co-routine is the common header to the 3rd and 4th templates.
832   */
833   if( pSelect ){
834     /* Data is coming from a SELECT or from a multi-row VALUES clause.
835     ** Generate a co-routine to run the SELECT. */
836     int regYield;       /* Register holding co-routine entry-point */
837     int addrTop;        /* Top of the co-routine */
838     int rc;             /* Result code */
839 
840     regYield = ++pParse->nMem;
841     addrTop = sqlite3VdbeCurrentAddr(v) + 1;
842     sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield, 0, addrTop);
843     sqlite3SelectDestInit(&dest, SRT_Coroutine, regYield);
844     dest.iSdst = bIdListInOrder ? regData : 0;
845     dest.nSdst = pTab->nCol;
846     rc = sqlite3Select(pParse, pSelect, &dest);
847     regFromSelect = dest.iSdst;
848     if( rc || db->mallocFailed || pParse->nErr ) goto insert_cleanup;
849     sqlite3VdbeEndCoroutine(v, regYield);
850     sqlite3VdbeJumpHere(v, addrTop - 1);                       /* label B: */
851     assert( pSelect->pEList );
852     nColumn = pSelect->pEList->nExpr;
853 
854     /* Set useTempTable to TRUE if the result of the SELECT statement
855     ** should be written into a temporary table (template 4).  Set to
856     ** FALSE if each output row of the SELECT can be written directly into
857     ** the destination table (template 3).
858     **
859     ** A temp table must be used if the table being updated is also one
860     ** of the tables being read by the SELECT statement.  Also use a
861     ** temp table in the case of row triggers.
862     */
863     if( pTrigger || readsTable(pParse, iDb, pTab) ){
864       useTempTable = 1;
865     }
866 
867     if( useTempTable ){
868       /* Invoke the coroutine to extract information from the SELECT
869       ** and add it to a transient table srcTab.  The code generated
870       ** here is from the 4th template:
871       **
872       **      B: open temp table
873       **      L: yield X, goto M at EOF
874       **         insert row from R..R+n into temp table
875       **         goto L
876       **      M: ...
877       */
878       int regRec;          /* Register to hold packed record */
879       int regTempRowid;    /* Register to hold temp table ROWID */
880       int addrL;           /* Label "L" */
881 
882       srcTab = pParse->nTab++;
883       regRec = sqlite3GetTempReg(pParse);
884       regTempRowid = sqlite3GetTempReg(pParse);
885       sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
886       addrL = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); VdbeCoverage(v);
887       sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
888       sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
889       sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
890       sqlite3VdbeGoto(v, addrL);
891       sqlite3VdbeJumpHere(v, addrL);
892       sqlite3ReleaseTempReg(pParse, regRec);
893       sqlite3ReleaseTempReg(pParse, regTempRowid);
894     }
895   }else{
896     /* This is the case if the data for the INSERT is coming from a
897     ** single-row VALUES clause
898     */
899     NameContext sNC;
900     memset(&sNC, 0, sizeof(sNC));
901     sNC.pParse = pParse;
902     srcTab = -1;
903     assert( useTempTable==0 );
904     if( pList ){
905       nColumn = pList->nExpr;
906       if( sqlite3ResolveExprListNames(&sNC, pList) ){
907         goto insert_cleanup;
908       }
909     }else{
910       nColumn = 0;
911     }
912   }
913 
914   /* If there is no IDLIST term but the table has an integer primary
915   ** key, the set the ipkColumn variable to the integer primary key
916   ** column index in the original table definition.
917   */
918   if( pColumn==0 && nColumn>0 ){
919     ipkColumn = pTab->iPKey;
920 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
921     if( ipkColumn>=0 && (pTab->tabFlags & TF_HasGenerated)!=0 ){
922       testcase( pTab->tabFlags & TF_HasVirtual );
923       testcase( pTab->tabFlags & TF_HasStored );
924       for(i=ipkColumn-1; i>=0; i--){
925         if( pTab->aCol[i].colFlags & COLFLAG_GENERATED ){
926           testcase( pTab->aCol[i].colFlags & COLFLAG_VIRTUAL );
927           testcase( pTab->aCol[i].colFlags & COLFLAG_STORED );
928           ipkColumn--;
929         }
930       }
931     }
932 #endif
933   }
934 
935   /* Make sure the number of columns in the source data matches the number
936   ** of columns to be inserted into the table.
937   */
938   for(i=0; i<pTab->nCol; i++){
939     if( pTab->aCol[i].colFlags & COLFLAG_NOINSERT ) nHidden++;
940   }
941   if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
942     sqlite3ErrorMsg(pParse,
943        "table %S has %d columns but %d values were supplied",
944        pTabList, 0, pTab->nCol-nHidden, nColumn);
945     goto insert_cleanup;
946   }
947   if( pColumn!=0 && nColumn!=pColumn->nId ){
948     sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
949     goto insert_cleanup;
950   }
951 
952   /* Initialize the count of rows to be inserted
953   */
954   if( (db->flags & SQLITE_CountRows)!=0
955    && !pParse->nested
956    && !pParse->pTriggerTab
957   ){
958     regRowCount = ++pParse->nMem;
959     sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
960   }
961 
962   /* If this is not a view, open the table and and all indices */
963   if( !isView ){
964     int nIdx;
965     nIdx = sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, -1, 0,
966                                       &iDataCur, &iIdxCur);
967     aRegIdx = sqlite3DbMallocRawNN(db, sizeof(int)*(nIdx+2));
968     if( aRegIdx==0 ){
969       goto insert_cleanup;
970     }
971     for(i=0, pIdx=pTab->pIndex; i<nIdx; pIdx=pIdx->pNext, i++){
972       assert( pIdx );
973       aRegIdx[i] = ++pParse->nMem;
974       pParse->nMem += pIdx->nColumn;
975     }
976     aRegIdx[i] = ++pParse->nMem;  /* Register to store the table record */
977   }
978 #ifndef SQLITE_OMIT_UPSERT
979   if( pUpsert ){
980     Upsert *pNx;
981     if( IsVirtual(pTab) ){
982       sqlite3ErrorMsg(pParse, "UPSERT not implemented for virtual table \"%s\"",
983               pTab->zName);
984       goto insert_cleanup;
985     }
986     if( pTab->pSelect ){
987       sqlite3ErrorMsg(pParse, "cannot UPSERT a view");
988       goto insert_cleanup;
989     }
990     if( sqlite3HasExplicitNulls(pParse, pUpsert->pUpsertTarget) ){
991       goto insert_cleanup;
992     }
993     pTabList->a[0].iCursor = iDataCur;
994     pNx = pUpsert;
995     do{
996       pNx->pUpsertSrc = pTabList;
997       pNx->regData = regData;
998       pNx->iDataCur = iDataCur;
999       pNx->iIdxCur = iIdxCur;
1000       if( pNx->pUpsertTarget ){
1001         sqlite3UpsertAnalyzeTarget(pParse, pTabList, pNx);
1002       }
1003       pNx = pNx->pNextUpsert;
1004     }while( pNx!=0 );
1005   }
1006 #endif
1007 
1008 
1009   /* This is the top of the main insertion loop */
1010   if( useTempTable ){
1011     /* This block codes the top of loop only.  The complete loop is the
1012     ** following pseudocode (template 4):
1013     **
1014     **         rewind temp table, if empty goto D
1015     **      C: loop over rows of intermediate table
1016     **           transfer values form intermediate table into <table>
1017     **         end loop
1018     **      D: ...
1019     */
1020     addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab); VdbeCoverage(v);
1021     addrCont = sqlite3VdbeCurrentAddr(v);
1022   }else if( pSelect ){
1023     /* This block codes the top of loop only.  The complete loop is the
1024     ** following pseudocode (template 3):
1025     **
1026     **      C: yield X, at EOF goto D
1027     **         insert the select result into <table> from R..R+n
1028     **         goto C
1029     **      D: ...
1030     */
1031     sqlite3VdbeReleaseRegisters(pParse, regData, pTab->nCol, 0, 0);
1032     addrInsTop = addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);
1033     VdbeCoverage(v);
1034     if( ipkColumn>=0 ){
1035       /* tag-20191021-001: If the INTEGER PRIMARY KEY is being generated by the
1036       ** SELECT, go ahead and copy the value into the rowid slot now, so that
1037       ** the value does not get overwritten by a NULL at tag-20191021-002. */
1038       sqlite3VdbeAddOp2(v, OP_Copy, regFromSelect+ipkColumn, regRowid);
1039     }
1040   }
1041 
1042   /* Compute data for ordinary columns of the new entry.  Values
1043   ** are written in storage order into registers starting with regData.
1044   ** Only ordinary columns are computed in this loop. The rowid
1045   ** (if there is one) is computed later and generated columns are
1046   ** computed after the rowid since they might depend on the value
1047   ** of the rowid.
1048   */
1049   nHidden = 0;
1050   iRegStore = regData;  assert( regData==regRowid+1 );
1051   for(i=0; i<pTab->nCol; i++, iRegStore++){
1052     int k;
1053     u32 colFlags;
1054     assert( i>=nHidden );
1055     if( i==pTab->iPKey ){
1056       /* tag-20191021-002: References to the INTEGER PRIMARY KEY are filled
1057       ** using the rowid. So put a NULL in the IPK slot of the record to avoid
1058       ** using excess space.  The file format definition requires this extra
1059       ** NULL - we cannot optimize further by skipping the column completely */
1060       sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore);
1061       continue;
1062     }
1063     if( ((colFlags = pTab->aCol[i].colFlags) & COLFLAG_NOINSERT)!=0 ){
1064       nHidden++;
1065       if( (colFlags & COLFLAG_VIRTUAL)!=0 ){
1066         /* Virtual columns do not participate in OP_MakeRecord.  So back up
1067         ** iRegStore by one slot to compensate for the iRegStore++ in the
1068         ** outer for() loop */
1069         iRegStore--;
1070         continue;
1071       }else if( (colFlags & COLFLAG_STORED)!=0 ){
1072         /* Stored columns are computed later.  But if there are BEFORE
1073         ** triggers, the slots used for stored columns will be OP_Copy-ed
1074         ** to a second block of registers, so the register needs to be
1075         ** initialized to NULL to avoid an uninitialized register read */
1076         if( tmask & TRIGGER_BEFORE ){
1077           sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore);
1078         }
1079         continue;
1080       }else if( pColumn==0 ){
1081         /* Hidden columns that are not explicitly named in the INSERT
1082         ** get there default value */
1083         sqlite3ExprCodeFactorable(pParse, pTab->aCol[i].pDflt, iRegStore);
1084         continue;
1085       }
1086     }
1087     if( pColumn ){
1088       for(j=0; j<pColumn->nId && pColumn->a[j].idx!=i; j++){}
1089       if( j>=pColumn->nId ){
1090         /* A column not named in the insert column list gets its
1091         ** default value */
1092         sqlite3ExprCodeFactorable(pParse, pTab->aCol[i].pDflt, iRegStore);
1093         continue;
1094       }
1095       k = j;
1096     }else if( nColumn==0 ){
1097       /* This is INSERT INTO ... DEFAULT VALUES.  Load the default value. */
1098       sqlite3ExprCodeFactorable(pParse, pTab->aCol[i].pDflt, iRegStore);
1099       continue;
1100     }else{
1101       k = i - nHidden;
1102     }
1103 
1104     if( useTempTable ){
1105       sqlite3VdbeAddOp3(v, OP_Column, srcTab, k, iRegStore);
1106     }else if( pSelect ){
1107       if( regFromSelect!=regData ){
1108         sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+k, iRegStore);
1109       }
1110     }else{
1111       sqlite3ExprCode(pParse, pList->a[k].pExpr, iRegStore);
1112     }
1113   }
1114 
1115 
1116   /* Run the BEFORE and INSTEAD OF triggers, if there are any
1117   */
1118   endOfLoop = sqlite3VdbeMakeLabel(pParse);
1119   if( tmask & TRIGGER_BEFORE ){
1120     int regCols = sqlite3GetTempRange(pParse, pTab->nCol+1);
1121 
1122     /* build the NEW.* reference row.  Note that if there is an INTEGER
1123     ** PRIMARY KEY into which a NULL is being inserted, that NULL will be
1124     ** translated into a unique ID for the row.  But on a BEFORE trigger,
1125     ** we do not know what the unique ID will be (because the insert has
1126     ** not happened yet) so we substitute a rowid of -1
1127     */
1128     if( ipkColumn<0 ){
1129       sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols);
1130     }else{
1131       int addr1;
1132       assert( !withoutRowid );
1133       if( useTempTable ){
1134         sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regCols);
1135       }else{
1136         assert( pSelect==0 );  /* Otherwise useTempTable is true */
1137         sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regCols);
1138       }
1139       addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regCols); VdbeCoverage(v);
1140       sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols);
1141       sqlite3VdbeJumpHere(v, addr1);
1142       sqlite3VdbeAddOp1(v, OP_MustBeInt, regCols); VdbeCoverage(v);
1143     }
1144 
1145     /* Cannot have triggers on a virtual table. If it were possible,
1146     ** this block would have to account for hidden column.
1147     */
1148     assert( !IsVirtual(pTab) );
1149 
1150     /* Copy the new data already generated. */
1151     assert( pTab->nNVCol>0 );
1152     sqlite3VdbeAddOp3(v, OP_Copy, regRowid+1, regCols+1, pTab->nNVCol-1);
1153 
1154 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
1155     /* Compute the new value for generated columns after all other
1156     ** columns have already been computed.  This must be done after
1157     ** computing the ROWID in case one of the generated columns
1158     ** refers to the ROWID. */
1159     if( pTab->tabFlags & TF_HasGenerated ){
1160       testcase( pTab->tabFlags & TF_HasVirtual );
1161       testcase( pTab->tabFlags & TF_HasStored );
1162       sqlite3ComputeGeneratedColumns(pParse, regCols+1, pTab);
1163     }
1164 #endif
1165 
1166     /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
1167     ** do not attempt any conversions before assembling the record.
1168     ** If this is a real table, attempt conversions as required by the
1169     ** table column affinities.
1170     */
1171     if( !isView ){
1172       sqlite3TableAffinity(v, pTab, regCols+1);
1173     }
1174 
1175     /* Fire BEFORE or INSTEAD OF triggers */
1176     sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE,
1177         pTab, regCols-pTab->nCol-1, onError, endOfLoop);
1178 
1179     sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol+1);
1180   }
1181 
1182   if( !isView ){
1183     if( IsVirtual(pTab) ){
1184       /* The row that the VUpdate opcode will delete: none */
1185       sqlite3VdbeAddOp2(v, OP_Null, 0, regIns);
1186     }
1187     if( ipkColumn>=0 ){
1188       /* Compute the new rowid */
1189       if( useTempTable ){
1190         sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regRowid);
1191       }else if( pSelect ){
1192         /* Rowid already initialized at tag-20191021-001 */
1193       }else{
1194         Expr *pIpk = pList->a[ipkColumn].pExpr;
1195         if( pIpk->op==TK_NULL && !IsVirtual(pTab) ){
1196           sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc);
1197           appendFlag = 1;
1198         }else{
1199           sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regRowid);
1200         }
1201       }
1202       /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
1203       ** to generate a unique primary key value.
1204       */
1205       if( !appendFlag ){
1206         int addr1;
1207         if( !IsVirtual(pTab) ){
1208           addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid); VdbeCoverage(v);
1209           sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc);
1210           sqlite3VdbeJumpHere(v, addr1);
1211         }else{
1212           addr1 = sqlite3VdbeCurrentAddr(v);
1213           sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, addr1+2); VdbeCoverage(v);
1214         }
1215         sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid); VdbeCoverage(v);
1216       }
1217     }else if( IsVirtual(pTab) || withoutRowid ){
1218       sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid);
1219     }else{
1220       sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc);
1221       appendFlag = 1;
1222     }
1223     autoIncStep(pParse, regAutoinc, regRowid);
1224 
1225 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
1226     /* Compute the new value for generated columns after all other
1227     ** columns have already been computed.  This must be done after
1228     ** computing the ROWID in case one of the generated columns
1229     ** is derived from the INTEGER PRIMARY KEY. */
1230     if( pTab->tabFlags & TF_HasGenerated ){
1231       sqlite3ComputeGeneratedColumns(pParse, regRowid+1, pTab);
1232     }
1233 #endif
1234 
1235     /* Generate code to check constraints and generate index keys and
1236     ** do the insertion.
1237     */
1238 #ifndef SQLITE_OMIT_VIRTUALTABLE
1239     if( IsVirtual(pTab) ){
1240       const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
1241       sqlite3VtabMakeWritable(pParse, pTab);
1242       sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB);
1243       sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
1244       sqlite3MayAbort(pParse);
1245     }else
1246 #endif
1247     {
1248       int isReplace;    /* Set to true if constraints may cause a replace */
1249       int bUseSeek;     /* True to use OPFLAG_SEEKRESULT */
1250       sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
1251           regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace, 0, pUpsert
1252       );
1253       sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0);
1254 
1255       /* Set the OPFLAG_USESEEKRESULT flag if either (a) there are no REPLACE
1256       ** constraints or (b) there are no triggers and this table is not a
1257       ** parent table in a foreign key constraint. It is safe to set the
1258       ** flag in the second case as if any REPLACE constraint is hit, an
1259       ** OP_Delete or OP_IdxDelete instruction will be executed on each
1260       ** cursor that is disturbed. And these instructions both clear the
1261       ** VdbeCursor.seekResult variable, disabling the OPFLAG_USESEEKRESULT
1262       ** functionality.  */
1263       bUseSeek = (isReplace==0 || !sqlite3VdbeHasSubProgram(v));
1264       sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
1265           regIns, aRegIdx, 0, appendFlag, bUseSeek
1266       );
1267     }
1268   }
1269 
1270   /* Update the count of rows that are inserted
1271   */
1272   if( regRowCount ){
1273     sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
1274   }
1275 
1276   if( pTrigger ){
1277     /* Code AFTER triggers */
1278     sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_AFTER,
1279         pTab, regData-2-pTab->nCol, onError, endOfLoop);
1280   }
1281 
1282   /* The bottom of the main insertion loop, if the data source
1283   ** is a SELECT statement.
1284   */
1285   sqlite3VdbeResolveLabel(v, endOfLoop);
1286   if( useTempTable ){
1287     sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont); VdbeCoverage(v);
1288     sqlite3VdbeJumpHere(v, addrInsTop);
1289     sqlite3VdbeAddOp1(v, OP_Close, srcTab);
1290   }else if( pSelect ){
1291     sqlite3VdbeGoto(v, addrCont);
1292 #ifdef SQLITE_DEBUG
1293     /* If we are jumping back to an OP_Yield that is preceded by an
1294     ** OP_ReleaseReg, set the p5 flag on the OP_Goto so that the
1295     ** OP_ReleaseReg will be included in the loop. */
1296     if( sqlite3VdbeGetOp(v, addrCont-1)->opcode==OP_ReleaseReg ){
1297       assert( sqlite3VdbeGetOp(v, addrCont)->opcode==OP_Yield );
1298       sqlite3VdbeChangeP5(v, 1);
1299     }
1300 #endif
1301     sqlite3VdbeJumpHere(v, addrInsTop);
1302   }
1303 
1304 insert_end:
1305   /* Update the sqlite_sequence table by storing the content of the
1306   ** maximum rowid counter values recorded while inserting into
1307   ** autoincrement tables.
1308   */
1309   if( pParse->nested==0 && pParse->pTriggerTab==0 ){
1310     sqlite3AutoincrementEnd(pParse);
1311   }
1312 
1313   /*
1314   ** Return the number of rows inserted. If this routine is
1315   ** generating code because of a call to sqlite3NestedParse(), do not
1316   ** invoke the callback function.
1317   */
1318   if( regRowCount ){
1319     sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
1320     sqlite3VdbeSetNumCols(v, 1);
1321     sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", SQLITE_STATIC);
1322   }
1323 
1324 insert_cleanup:
1325   sqlite3SrcListDelete(db, pTabList);
1326   sqlite3ExprListDelete(db, pList);
1327   sqlite3UpsertDelete(db, pUpsert);
1328   sqlite3SelectDelete(db, pSelect);
1329   sqlite3IdListDelete(db, pColumn);
1330   sqlite3DbFree(db, aRegIdx);
1331 }
1332 
1333 /* Make sure "isView" and other macros defined above are undefined. Otherwise
1334 ** they may interfere with compilation of other functions in this file
1335 ** (or in another file, if this file becomes part of the amalgamation).  */
1336 #ifdef isView
1337  #undef isView
1338 #endif
1339 #ifdef pTrigger
1340  #undef pTrigger
1341 #endif
1342 #ifdef tmask
1343  #undef tmask
1344 #endif
1345 
1346 /*
1347 ** Meanings of bits in of pWalker->eCode for
1348 ** sqlite3ExprReferencesUpdatedColumn()
1349 */
1350 #define CKCNSTRNT_COLUMN   0x01    /* CHECK constraint uses a changing column */
1351 #define CKCNSTRNT_ROWID    0x02    /* CHECK constraint references the ROWID */
1352 
1353 /* This is the Walker callback from sqlite3ExprReferencesUpdatedColumn().
1354 *  Set bit 0x01 of pWalker->eCode if pWalker->eCode to 0 and if this
1355 ** expression node references any of the
1356 ** columns that are being modifed by an UPDATE statement.
1357 */
1358 static int checkConstraintExprNode(Walker *pWalker, Expr *pExpr){
1359   if( pExpr->op==TK_COLUMN ){
1360     assert( pExpr->iColumn>=0 || pExpr->iColumn==-1 );
1361     if( pExpr->iColumn>=0 ){
1362       if( pWalker->u.aiCol[pExpr->iColumn]>=0 ){
1363         pWalker->eCode |= CKCNSTRNT_COLUMN;
1364       }
1365     }else{
1366       pWalker->eCode |= CKCNSTRNT_ROWID;
1367     }
1368   }
1369   return WRC_Continue;
1370 }
1371 
1372 /*
1373 ** pExpr is a CHECK constraint on a row that is being UPDATE-ed.  The
1374 ** only columns that are modified by the UPDATE are those for which
1375 ** aiChng[i]>=0, and also the ROWID is modified if chngRowid is true.
1376 **
1377 ** Return true if CHECK constraint pExpr uses any of the
1378 ** changing columns (or the rowid if it is changing).  In other words,
1379 ** return true if this CHECK constraint must be validated for
1380 ** the new row in the UPDATE statement.
1381 **
1382 ** 2018-09-15: pExpr might also be an expression for an index-on-expressions.
1383 ** The operation of this routine is the same - return true if an only if
1384 ** the expression uses one or more of columns identified by the second and
1385 ** third arguments.
1386 */
1387 int sqlite3ExprReferencesUpdatedColumn(
1388   Expr *pExpr,    /* The expression to be checked */
1389   int *aiChng,    /* aiChng[x]>=0 if column x changed by the UPDATE */
1390   int chngRowid   /* True if UPDATE changes the rowid */
1391 ){
1392   Walker w;
1393   memset(&w, 0, sizeof(w));
1394   w.eCode = 0;
1395   w.xExprCallback = checkConstraintExprNode;
1396   w.u.aiCol = aiChng;
1397   sqlite3WalkExpr(&w, pExpr);
1398   if( !chngRowid ){
1399     testcase( (w.eCode & CKCNSTRNT_ROWID)!=0 );
1400     w.eCode &= ~CKCNSTRNT_ROWID;
1401   }
1402   testcase( w.eCode==0 );
1403   testcase( w.eCode==CKCNSTRNT_COLUMN );
1404   testcase( w.eCode==CKCNSTRNT_ROWID );
1405   testcase( w.eCode==(CKCNSTRNT_ROWID|CKCNSTRNT_COLUMN) );
1406   return w.eCode!=0;
1407 }
1408 
1409 /*
1410 ** The sqlite3GenerateConstraintChecks() routine usually wants to visit
1411 ** the indexes of a table in the order provided in the Table->pIndex list.
1412 ** However, sometimes (rarely - when there is an upsert) it wants to visit
1413 ** the indexes in a different order.  The following data structures accomplish
1414 ** this.
1415 **
1416 ** The IndexIterator object is used to walk through all of the indexes
1417 ** of a table in either Index.pNext order, or in some other order established
1418 ** by an array of IndexListTerm objects.
1419 */
1420 typedef struct IndexListTerm IndexListTerm;
1421 typedef struct IndexIterator IndexIterator;
1422 struct IndexIterator {
1423   int eType;    /* 0 for Index.pNext list.  1 for an array of IndexListTerm */
1424   int i;        /* Index of the current item from the list */
1425   union {
1426     struct {    /* Use this object for eType==0: A Index.pNext list */
1427       Index *pIdx;   /* The current Index */
1428     } lx;
1429     struct {    /* Use this object for eType==1; Array of IndexListTerm */
1430       int nIdx;               /* Size of the array */
1431       IndexListTerm *aIdx;    /* Array of IndexListTerms */
1432     } ax;
1433   } u;
1434 };
1435 
1436 /* When IndexIterator.eType==1, then each index is an array of instances
1437 ** of the following object
1438 */
1439 struct IndexListTerm {
1440   Index *p;  /* The index */
1441   int ix;    /* Which entry in the original Table.pIndex list is this index*/
1442 };
1443 
1444 /* Return the first index on the list */
1445 static Index *indexIteratorFirst(IndexIterator *pIter, int *pIx){
1446   assert( pIter->i==0 );
1447   if( pIter->eType ){
1448     *pIx = pIter->u.ax.aIdx[0].ix;
1449     return pIter->u.ax.aIdx[0].p;
1450   }else{
1451     *pIx = 0;
1452     return pIter->u.lx.pIdx;
1453   }
1454 }
1455 
1456 /* Return the next index from the list.  Return NULL when out of indexes */
1457 static Index *indexIteratorNext(IndexIterator *pIter, int *pIx){
1458   if( pIter->eType ){
1459     int i = ++pIter->i;
1460     if( i>=pIter->u.ax.nIdx ){
1461       *pIx = i;
1462       return 0;
1463     }
1464     *pIx = pIter->u.ax.aIdx[i].ix;
1465     return pIter->u.ax.aIdx[i].p;
1466   }else{
1467     ++(*pIx);
1468     pIter->u.lx.pIdx = pIter->u.lx.pIdx->pNext;
1469     return pIter->u.lx.pIdx;
1470   }
1471 }
1472 
1473 /*
1474 ** Generate code to do constraint checks prior to an INSERT or an UPDATE
1475 ** on table pTab.
1476 **
1477 ** The regNewData parameter is the first register in a range that contains
1478 ** the data to be inserted or the data after the update.  There will be
1479 ** pTab->nCol+1 registers in this range.  The first register (the one
1480 ** that regNewData points to) will contain the new rowid, or NULL in the
1481 ** case of a WITHOUT ROWID table.  The second register in the range will
1482 ** contain the content of the first table column.  The third register will
1483 ** contain the content of the second table column.  And so forth.
1484 **
1485 ** The regOldData parameter is similar to regNewData except that it contains
1486 ** the data prior to an UPDATE rather than afterwards.  regOldData is zero
1487 ** for an INSERT.  This routine can distinguish between UPDATE and INSERT by
1488 ** checking regOldData for zero.
1489 **
1490 ** For an UPDATE, the pkChng boolean is true if the true primary key (the
1491 ** rowid for a normal table or the PRIMARY KEY for a WITHOUT ROWID table)
1492 ** might be modified by the UPDATE.  If pkChng is false, then the key of
1493 ** the iDataCur content table is guaranteed to be unchanged by the UPDATE.
1494 **
1495 ** For an INSERT, the pkChng boolean indicates whether or not the rowid
1496 ** was explicitly specified as part of the INSERT statement.  If pkChng
1497 ** is zero, it means that the either rowid is computed automatically or
1498 ** that the table is a WITHOUT ROWID table and has no rowid.  On an INSERT,
1499 ** pkChng will only be true if the INSERT statement provides an integer
1500 ** value for either the rowid column or its INTEGER PRIMARY KEY alias.
1501 **
1502 ** The code generated by this routine will store new index entries into
1503 ** registers identified by aRegIdx[].  No index entry is created for
1504 ** indices where aRegIdx[i]==0.  The order of indices in aRegIdx[] is
1505 ** the same as the order of indices on the linked list of indices
1506 ** at pTab->pIndex.
1507 **
1508 ** (2019-05-07) The generated code also creates a new record for the
1509 ** main table, if pTab is a rowid table, and stores that record in the
1510 ** register identified by aRegIdx[nIdx] - in other words in the first
1511 ** entry of aRegIdx[] past the last index.  It is important that the
1512 ** record be generated during constraint checks to avoid affinity changes
1513 ** to the register content that occur after constraint checks but before
1514 ** the new record is inserted.
1515 **
1516 ** The caller must have already opened writeable cursors on the main
1517 ** table and all applicable indices (that is to say, all indices for which
1518 ** aRegIdx[] is not zero).  iDataCur is the cursor for the main table when
1519 ** inserting or updating a rowid table, or the cursor for the PRIMARY KEY
1520 ** index when operating on a WITHOUT ROWID table.  iIdxCur is the cursor
1521 ** for the first index in the pTab->pIndex list.  Cursors for other indices
1522 ** are at iIdxCur+N for the N-th element of the pTab->pIndex list.
1523 **
1524 ** This routine also generates code to check constraints.  NOT NULL,
1525 ** CHECK, and UNIQUE constraints are all checked.  If a constraint fails,
1526 ** then the appropriate action is performed.  There are five possible
1527 ** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
1528 **
1529 **  Constraint type  Action       What Happens
1530 **  ---------------  ----------   ----------------------------------------
1531 **  any              ROLLBACK     The current transaction is rolled back and
1532 **                                sqlite3_step() returns immediately with a
1533 **                                return code of SQLITE_CONSTRAINT.
1534 **
1535 **  any              ABORT        Back out changes from the current command
1536 **                                only (do not do a complete rollback) then
1537 **                                cause sqlite3_step() to return immediately
1538 **                                with SQLITE_CONSTRAINT.
1539 **
1540 **  any              FAIL         Sqlite3_step() returns immediately with a
1541 **                                return code of SQLITE_CONSTRAINT.  The
1542 **                                transaction is not rolled back and any
1543 **                                changes to prior rows are retained.
1544 **
1545 **  any              IGNORE       The attempt in insert or update the current
1546 **                                row is skipped, without throwing an error.
1547 **                                Processing continues with the next row.
1548 **                                (There is an immediate jump to ignoreDest.)
1549 **
1550 **  NOT NULL         REPLACE      The NULL value is replace by the default
1551 **                                value for that column.  If the default value
1552 **                                is NULL, the action is the same as ABORT.
1553 **
1554 **  UNIQUE           REPLACE      The other row that conflicts with the row
1555 **                                being inserted is removed.
1556 **
1557 **  CHECK            REPLACE      Illegal.  The results in an exception.
1558 **
1559 ** Which action to take is determined by the overrideError parameter.
1560 ** Or if overrideError==OE_Default, then the pParse->onError parameter
1561 ** is used.  Or if pParse->onError==OE_Default then the onError value
1562 ** for the constraint is used.
1563 */
1564 void sqlite3GenerateConstraintChecks(
1565   Parse *pParse,       /* The parser context */
1566   Table *pTab,         /* The table being inserted or updated */
1567   int *aRegIdx,        /* Use register aRegIdx[i] for index i.  0 for unused */
1568   int iDataCur,        /* Canonical data cursor (main table or PK index) */
1569   int iIdxCur,         /* First index cursor */
1570   int regNewData,      /* First register in a range holding values to insert */
1571   int regOldData,      /* Previous content.  0 for INSERTs */
1572   u8 pkChng,           /* Non-zero if the rowid or PRIMARY KEY changed */
1573   u8 overrideError,    /* Override onError to this if not OE_Default */
1574   int ignoreDest,      /* Jump to this label on an OE_Ignore resolution */
1575   int *pbMayReplace,   /* OUT: Set to true if constraint may cause a replace */
1576   int *aiChng,         /* column i is unchanged if aiChng[i]<0 */
1577   Upsert *pUpsert      /* ON CONFLICT clauses, if any.  NULL otherwise */
1578 ){
1579   Vdbe *v;             /* VDBE under constrution */
1580   Index *pIdx;         /* Pointer to one of the indices */
1581   Index *pPk = 0;      /* The PRIMARY KEY index for WITHOUT ROWID tables */
1582   sqlite3 *db;         /* Database connection */
1583   int i;               /* loop counter */
1584   int ix;              /* Index loop counter */
1585   int nCol;            /* Number of columns */
1586   int onError;         /* Conflict resolution strategy */
1587   int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */
1588   int nPkField;        /* Number of fields in PRIMARY KEY. 1 for ROWID tables */
1589   Upsert *pUpsertClause = 0;  /* The specific ON CONFLICT clause for pIdx */
1590   u8 isUpdate;           /* True if this is an UPDATE operation */
1591   u8 bAffinityDone = 0;  /* True if the OP_Affinity operation has been run */
1592   int upsertIpkReturn = 0; /* Address of Goto at end of IPK uniqueness check */
1593   int upsertIpkDelay = 0;  /* Address of Goto to bypass initial IPK check */
1594   int ipkTop = 0;        /* Top of the IPK uniqueness check */
1595   int ipkBottom = 0;     /* OP_Goto at the end of the IPK uniqueness check */
1596   /* Variables associated with retesting uniqueness constraints after
1597   ** replace triggers fire have run */
1598   int regTrigCnt;       /* Register used to count replace trigger invocations */
1599   int addrRecheck = 0;  /* Jump here to recheck all uniqueness constraints */
1600   int lblRecheckOk = 0; /* Each recheck jumps to this label if it passes */
1601   Trigger *pTrigger;    /* List of DELETE triggers on the table pTab */
1602   int nReplaceTrig = 0; /* Number of replace triggers coded */
1603   IndexIterator sIdxIter;  /* Index iterator */
1604 
1605   isUpdate = regOldData!=0;
1606   db = pParse->db;
1607   v = pParse->pVdbe;
1608   assert( v!=0 );
1609   assert( pTab->pSelect==0 );  /* This table is not a VIEW */
1610   nCol = pTab->nCol;
1611 
1612   /* pPk is the PRIMARY KEY index for WITHOUT ROWID tables and NULL for
1613   ** normal rowid tables.  nPkField is the number of key fields in the
1614   ** pPk index or 1 for a rowid table.  In other words, nPkField is the
1615   ** number of fields in the true primary key of the table. */
1616   if( HasRowid(pTab) ){
1617     pPk = 0;
1618     nPkField = 1;
1619   }else{
1620     pPk = sqlite3PrimaryKeyIndex(pTab);
1621     nPkField = pPk->nKeyCol;
1622   }
1623 
1624   /* Record that this module has started */
1625   VdbeModuleComment((v, "BEGIN: GenCnstCks(%d,%d,%d,%d,%d)",
1626                      iDataCur, iIdxCur, regNewData, regOldData, pkChng));
1627 
1628   /* Test all NOT NULL constraints.
1629   */
1630   if( pTab->tabFlags & TF_HasNotNull ){
1631     int b2ndPass = 0;         /* True if currently running 2nd pass */
1632     int nSeenReplace = 0;     /* Number of ON CONFLICT REPLACE operations */
1633     int nGenerated = 0;       /* Number of generated columns with NOT NULL */
1634     while(1){  /* Make 2 passes over columns. Exit loop via "break" */
1635       for(i=0; i<nCol; i++){
1636         int iReg;                        /* Register holding column value */
1637         Column *pCol = &pTab->aCol[i];   /* The column to check for NOT NULL */
1638         int isGenerated;                 /* non-zero if column is generated */
1639         onError = pCol->notNull;
1640         if( onError==OE_None ) continue; /* No NOT NULL on this column */
1641         if( i==pTab->iPKey ){
1642           continue;        /* ROWID is never NULL */
1643         }
1644         isGenerated = pCol->colFlags & COLFLAG_GENERATED;
1645         if( isGenerated && !b2ndPass ){
1646           nGenerated++;
1647           continue;        /* Generated columns processed on 2nd pass */
1648         }
1649         if( aiChng && aiChng[i]<0 && !isGenerated ){
1650           /* Do not check NOT NULL on columns that do not change */
1651           continue;
1652         }
1653         if( overrideError!=OE_Default ){
1654           onError = overrideError;
1655         }else if( onError==OE_Default ){
1656           onError = OE_Abort;
1657         }
1658         if( onError==OE_Replace ){
1659           if( b2ndPass        /* REPLACE becomes ABORT on the 2nd pass */
1660            || pCol->pDflt==0  /* REPLACE is ABORT if no DEFAULT value */
1661           ){
1662             testcase( pCol->colFlags & COLFLAG_VIRTUAL );
1663             testcase( pCol->colFlags & COLFLAG_STORED );
1664             testcase( pCol->colFlags & COLFLAG_GENERATED );
1665             onError = OE_Abort;
1666           }else{
1667             assert( !isGenerated );
1668           }
1669         }else if( b2ndPass && !isGenerated ){
1670           continue;
1671         }
1672         assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
1673             || onError==OE_Ignore || onError==OE_Replace );
1674         testcase( i!=sqlite3TableColumnToStorage(pTab, i) );
1675         iReg = sqlite3TableColumnToStorage(pTab, i) + regNewData + 1;
1676         switch( onError ){
1677           case OE_Replace: {
1678             int addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, iReg);
1679             VdbeCoverage(v);
1680             assert( (pCol->colFlags & COLFLAG_GENERATED)==0 );
1681             nSeenReplace++;
1682             sqlite3ExprCodeCopy(pParse, pCol->pDflt, iReg);
1683             sqlite3VdbeJumpHere(v, addr1);
1684             break;
1685           }
1686           case OE_Abort:
1687             sqlite3MayAbort(pParse);
1688             /* no break */ deliberate_fall_through
1689           case OE_Rollback:
1690           case OE_Fail: {
1691             char *zMsg = sqlite3MPrintf(db, "%s.%s", pTab->zName,
1692                                         pCol->zName);
1693             sqlite3VdbeAddOp3(v, OP_HaltIfNull, SQLITE_CONSTRAINT_NOTNULL,
1694                               onError, iReg);
1695             sqlite3VdbeAppendP4(v, zMsg, P4_DYNAMIC);
1696             sqlite3VdbeChangeP5(v, P5_ConstraintNotNull);
1697             VdbeCoverage(v);
1698             break;
1699           }
1700           default: {
1701             assert( onError==OE_Ignore );
1702             sqlite3VdbeAddOp2(v, OP_IsNull, iReg, ignoreDest);
1703             VdbeCoverage(v);
1704             break;
1705           }
1706         } /* end switch(onError) */
1707       } /* end loop i over columns */
1708       if( nGenerated==0 && nSeenReplace==0 ){
1709         /* If there are no generated columns with NOT NULL constraints
1710         ** and no NOT NULL ON CONFLICT REPLACE constraints, then a single
1711         ** pass is sufficient */
1712         break;
1713       }
1714       if( b2ndPass ) break;  /* Never need more than 2 passes */
1715       b2ndPass = 1;
1716 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
1717       if( nSeenReplace>0 && (pTab->tabFlags & TF_HasGenerated)!=0 ){
1718         /* If any NOT NULL ON CONFLICT REPLACE constraints fired on the
1719         ** first pass, recomputed values for all generated columns, as
1720         ** those values might depend on columns affected by the REPLACE.
1721         */
1722         sqlite3ComputeGeneratedColumns(pParse, regNewData+1, pTab);
1723       }
1724 #endif
1725     } /* end of 2-pass loop */
1726   } /* end if( has-not-null-constraints ) */
1727 
1728   /* Test all CHECK constraints
1729   */
1730 #ifndef SQLITE_OMIT_CHECK
1731   if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){
1732     ExprList *pCheck = pTab->pCheck;
1733     pParse->iSelfTab = -(regNewData+1);
1734     onError = overrideError!=OE_Default ? overrideError : OE_Abort;
1735     for(i=0; i<pCheck->nExpr; i++){
1736       int allOk;
1737       Expr *pCopy;
1738       Expr *pExpr = pCheck->a[i].pExpr;
1739       if( aiChng
1740        && !sqlite3ExprReferencesUpdatedColumn(pExpr, aiChng, pkChng)
1741       ){
1742         /* The check constraints do not reference any of the columns being
1743         ** updated so there is no point it verifying the check constraint */
1744         continue;
1745       }
1746       if( bAffinityDone==0 ){
1747         sqlite3TableAffinity(v, pTab, regNewData+1);
1748         bAffinityDone = 1;
1749       }
1750       allOk = sqlite3VdbeMakeLabel(pParse);
1751       sqlite3VdbeVerifyAbortable(v, onError);
1752       pCopy = sqlite3ExprDup(db, pExpr, 0);
1753       if( !db->mallocFailed ){
1754         sqlite3ExprIfTrue(pParse, pCopy, allOk, SQLITE_JUMPIFNULL);
1755       }
1756       sqlite3ExprDelete(db, pCopy);
1757       if( onError==OE_Ignore ){
1758         sqlite3VdbeGoto(v, ignoreDest);
1759       }else{
1760         char *zName = pCheck->a[i].zEName;
1761         assert( zName!=0 || pParse->db->mallocFailed );
1762         if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-26383-51744 */
1763         sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_CHECK,
1764                               onError, zName, P4_TRANSIENT,
1765                               P5_ConstraintCheck);
1766       }
1767       sqlite3VdbeResolveLabel(v, allOk);
1768     }
1769     pParse->iSelfTab = 0;
1770   }
1771 #endif /* !defined(SQLITE_OMIT_CHECK) */
1772 
1773   /* UNIQUE and PRIMARY KEY constraints should be handled in the following
1774   ** order:
1775   **
1776   **   (1)  OE_Update
1777   **   (2)  OE_Abort, OE_Fail, OE_Rollback, OE_Ignore
1778   **   (3)  OE_Replace
1779   **
1780   ** OE_Fail and OE_Ignore must happen before any changes are made.
1781   ** OE_Update guarantees that only a single row will change, so it
1782   ** must happen before OE_Replace.  Technically, OE_Abort and OE_Rollback
1783   ** could happen in any order, but they are grouped up front for
1784   ** convenience.
1785   **
1786   ** 2018-08-14: Ticket https://www.sqlite.org/src/info/908f001483982c43
1787   ** The order of constraints used to have OE_Update as (2) and OE_Abort
1788   ** and so forth as (1). But apparently PostgreSQL checks the OE_Update
1789   ** constraint before any others, so it had to be moved.
1790   **
1791   ** Constraint checking code is generated in this order:
1792   **   (A)  The rowid constraint
1793   **   (B)  Unique index constraints that do not have OE_Replace as their
1794   **        default conflict resolution strategy
1795   **   (C)  Unique index that do use OE_Replace by default.
1796   **
1797   ** The ordering of (2) and (3) is accomplished by making sure the linked
1798   ** list of indexes attached to a table puts all OE_Replace indexes last
1799   ** in the list.  See sqlite3CreateIndex() for where that happens.
1800   */
1801   sIdxIter.eType = 0;
1802   sIdxIter.i = 0;
1803   sIdxIter.u.ax.aIdx = 0;  /* Silence harmless compiler warning */
1804   sIdxIter.u.lx.pIdx = pTab->pIndex;
1805   if( pUpsert ){
1806     if( pUpsert->pUpsertTarget==0 ){
1807       /* There is just on ON CONFLICT clause and it has no constraint-target */
1808       assert( pUpsert->pNextUpsert==0 );
1809       if( pUpsert->isDoUpdate==0 ){
1810         /* A single ON CONFLICT DO NOTHING clause, without a constraint-target.
1811         ** Make all unique constraint resolution be OE_Ignore */
1812         overrideError = OE_Ignore;
1813         pUpsert = 0;
1814       }else{
1815         /* A single ON CONFLICT DO UPDATE.  Make all resolutions OE_Update */
1816         overrideError = OE_Update;
1817       }
1818     }else if( pTab->pIndex!=0 ){
1819       /* Otherwise, we'll need to run the IndexListTerm array version of the
1820       ** iterator to ensure that all of the ON CONFLICT conditions are
1821       ** checked first and in order. */
1822       int nIdx, jj;
1823       u64 nByte;
1824       Upsert *pTerm;
1825       u8 *bUsed;
1826       for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
1827          assert( aRegIdx[nIdx]>0 );
1828       }
1829       sIdxIter.eType = 1;
1830       sIdxIter.u.ax.nIdx = nIdx;
1831       nByte = (sizeof(IndexListTerm)+1)*nIdx + nIdx;
1832       sIdxIter.u.ax.aIdx = sqlite3DbMallocZero(db, nByte);
1833       if( sIdxIter.u.ax.aIdx==0 ) return; /* OOM */
1834       bUsed = (u8*)&sIdxIter.u.ax.aIdx[nIdx];
1835       pUpsert->pToFree = sIdxIter.u.ax.aIdx;
1836       for(i=0, pTerm=pUpsert; pTerm; pTerm=pTerm->pNextUpsert){
1837         if( pTerm->pUpsertTarget==0 ) break;
1838         if( pTerm->pUpsertIdx==0 ) continue;  /* Skip ON CONFLICT for the IPK */
1839         jj = 0;
1840         pIdx = pTab->pIndex;
1841         while( ALWAYS(pIdx!=0) && pIdx!=pTerm->pUpsertIdx ){
1842            pIdx = pIdx->pNext;
1843            jj++;
1844         }
1845         if( bUsed[jj] ) continue; /* Duplicate ON CONFLICT clause ignored */
1846         bUsed[jj] = 1;
1847         sIdxIter.u.ax.aIdx[i].p = pIdx;
1848         sIdxIter.u.ax.aIdx[i].ix = jj;
1849         i++;
1850       }
1851       for(jj=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, jj++){
1852         if( bUsed[jj] ) continue;
1853         sIdxIter.u.ax.aIdx[i].p = pIdx;
1854         sIdxIter.u.ax.aIdx[i].ix = jj;
1855         i++;
1856       }
1857       assert( i==nIdx );
1858     }
1859   }
1860 
1861   /* Determine if it is possible that triggers (either explicitly coded
1862   ** triggers or FK resolution actions) might run as a result of deletes
1863   ** that happen when OE_Replace conflict resolution occurs. (Call these
1864   ** "replace triggers".)  If any replace triggers run, we will need to
1865   ** recheck all of the uniqueness constraints after they have all run.
1866   ** But on the recheck, the resolution is OE_Abort instead of OE_Replace.
1867   **
1868   ** If replace triggers are a possibility, then
1869   **
1870   **   (1) Allocate register regTrigCnt and initialize it to zero.
1871   **       That register will count the number of replace triggers that
1872   **       fire.  Constraint recheck only occurs if the number is positive.
1873   **   (2) Initialize pTrigger to the list of all DELETE triggers on pTab.
1874   **   (3) Initialize addrRecheck and lblRecheckOk
1875   **
1876   ** The uniqueness rechecking code will create a series of tests to run
1877   ** in a second pass.  The addrRecheck and lblRecheckOk variables are
1878   ** used to link together these tests which are separated from each other
1879   ** in the generate bytecode.
1880   */
1881   if( (db->flags & (SQLITE_RecTriggers|SQLITE_ForeignKeys))==0 ){
1882     /* There are not DELETE triggers nor FK constraints.  No constraint
1883     ** rechecks are needed. */
1884     pTrigger = 0;
1885     regTrigCnt = 0;
1886   }else{
1887     if( db->flags&SQLITE_RecTriggers ){
1888       pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
1889       regTrigCnt = pTrigger!=0 || sqlite3FkRequired(pParse, pTab, 0, 0);
1890     }else{
1891       pTrigger = 0;
1892       regTrigCnt = sqlite3FkRequired(pParse, pTab, 0, 0);
1893     }
1894     if( regTrigCnt ){
1895       /* Replace triggers might exist.  Allocate the counter and
1896       ** initialize it to zero. */
1897       regTrigCnt = ++pParse->nMem;
1898       sqlite3VdbeAddOp2(v, OP_Integer, 0, regTrigCnt);
1899       VdbeComment((v, "trigger count"));
1900       lblRecheckOk = sqlite3VdbeMakeLabel(pParse);
1901       addrRecheck = lblRecheckOk;
1902     }
1903   }
1904 
1905   /* If rowid is changing, make sure the new rowid does not previously
1906   ** exist in the table.
1907   */
1908   if( pkChng && pPk==0 ){
1909     int addrRowidOk = sqlite3VdbeMakeLabel(pParse);
1910 
1911     /* Figure out what action to take in case of a rowid collision */
1912     onError = pTab->keyConf;
1913     if( overrideError!=OE_Default ){
1914       onError = overrideError;
1915     }else if( onError==OE_Default ){
1916       onError = OE_Abort;
1917     }
1918 
1919     /* figure out whether or not upsert applies in this case */
1920     if( pUpsert ){
1921       pUpsertClause = sqlite3UpsertOfIndex(pUpsert,0);
1922       if( pUpsertClause!=0 ){
1923         if( pUpsertClause->isDoUpdate==0 ){
1924           onError = OE_Ignore;  /* DO NOTHING is the same as INSERT OR IGNORE */
1925         }else{
1926           onError = OE_Update;  /* DO UPDATE */
1927         }
1928       }
1929       if( pUpsertClause!=pUpsert ){
1930         /* The first ON CONFLICT clause has a conflict target other than
1931         ** the IPK.  We have to jump ahead to that first ON CONFLICT clause
1932         ** and then come back here and deal with the IPK afterwards */
1933         upsertIpkDelay = sqlite3VdbeAddOp0(v, OP_Goto);
1934       }
1935     }
1936 
1937     /* If the response to a rowid conflict is REPLACE but the response
1938     ** to some other UNIQUE constraint is FAIL or IGNORE, then we need
1939     ** to defer the running of the rowid conflict checking until after
1940     ** the UNIQUE constraints have run.
1941     */
1942     if( onError==OE_Replace      /* IPK rule is REPLACE */
1943      && onError!=overrideError   /* Rules for other constraints are different */
1944      && pTab->pIndex             /* There exist other constraints */
1945     ){
1946       ipkTop = sqlite3VdbeAddOp0(v, OP_Goto)+1;
1947       VdbeComment((v, "defer IPK REPLACE until last"));
1948     }
1949 
1950     if( isUpdate ){
1951       /* pkChng!=0 does not mean that the rowid has changed, only that
1952       ** it might have changed.  Skip the conflict logic below if the rowid
1953       ** is unchanged. */
1954       sqlite3VdbeAddOp3(v, OP_Eq, regNewData, addrRowidOk, regOldData);
1955       sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
1956       VdbeCoverage(v);
1957     }
1958 
1959     /* Check to see if the new rowid already exists in the table.  Skip
1960     ** the following conflict logic if it does not. */
1961     VdbeNoopComment((v, "uniqueness check for ROWID"));
1962     sqlite3VdbeVerifyAbortable(v, onError);
1963     sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRowidOk, regNewData);
1964     VdbeCoverage(v);
1965 
1966     switch( onError ){
1967       default: {
1968         onError = OE_Abort;
1969         /* no break */ deliberate_fall_through
1970       }
1971       case OE_Rollback:
1972       case OE_Abort:
1973       case OE_Fail: {
1974         testcase( onError==OE_Rollback );
1975         testcase( onError==OE_Abort );
1976         testcase( onError==OE_Fail );
1977         sqlite3RowidConstraint(pParse, onError, pTab);
1978         break;
1979       }
1980       case OE_Replace: {
1981         /* If there are DELETE triggers on this table and the
1982         ** recursive-triggers flag is set, call GenerateRowDelete() to
1983         ** remove the conflicting row from the table. This will fire
1984         ** the triggers and remove both the table and index b-tree entries.
1985         **
1986         ** Otherwise, if there are no triggers or the recursive-triggers
1987         ** flag is not set, but the table has one or more indexes, call
1988         ** GenerateRowIndexDelete(). This removes the index b-tree entries
1989         ** only. The table b-tree entry will be replaced by the new entry
1990         ** when it is inserted.
1991         **
1992         ** If either GenerateRowDelete() or GenerateRowIndexDelete() is called,
1993         ** also invoke MultiWrite() to indicate that this VDBE may require
1994         ** statement rollback (if the statement is aborted after the delete
1995         ** takes place). Earlier versions called sqlite3MultiWrite() regardless,
1996         ** but being more selective here allows statements like:
1997         **
1998         **   REPLACE INTO t(rowid) VALUES($newrowid)
1999         **
2000         ** to run without a statement journal if there are no indexes on the
2001         ** table.
2002         */
2003         if( regTrigCnt ){
2004           sqlite3MultiWrite(pParse);
2005           sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
2006                                    regNewData, 1, 0, OE_Replace, 1, -1);
2007           sqlite3VdbeAddOp2(v, OP_AddImm, regTrigCnt, 1); /* incr trigger cnt */
2008           nReplaceTrig++;
2009         }else{
2010 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
2011           assert( HasRowid(pTab) );
2012           /* This OP_Delete opcode fires the pre-update-hook only. It does
2013           ** not modify the b-tree. It is more efficient to let the coming
2014           ** OP_Insert replace the existing entry than it is to delete the
2015           ** existing entry and then insert a new one. */
2016           sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, OPFLAG_ISNOOP);
2017           sqlite3VdbeAppendP4(v, pTab, P4_TABLE);
2018 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
2019           if( pTab->pIndex ){
2020             sqlite3MultiWrite(pParse);
2021             sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,-1);
2022           }
2023         }
2024         seenReplace = 1;
2025         break;
2026       }
2027 #ifndef SQLITE_OMIT_UPSERT
2028       case OE_Update: {
2029         sqlite3UpsertDoUpdate(pParse, pUpsert, pTab, 0, iDataCur);
2030         /* no break */ deliberate_fall_through
2031       }
2032 #endif
2033       case OE_Ignore: {
2034         testcase( onError==OE_Ignore );
2035         sqlite3VdbeGoto(v, ignoreDest);
2036         break;
2037       }
2038     }
2039     sqlite3VdbeResolveLabel(v, addrRowidOk);
2040     if( pUpsert && pUpsertClause!=pUpsert ){
2041       upsertIpkReturn = sqlite3VdbeAddOp0(v, OP_Goto);
2042     }else if( ipkTop ){
2043       ipkBottom = sqlite3VdbeAddOp0(v, OP_Goto);
2044       sqlite3VdbeJumpHere(v, ipkTop-1);
2045     }
2046   }
2047 
2048   /* Test all UNIQUE constraints by creating entries for each UNIQUE
2049   ** index and making sure that duplicate entries do not already exist.
2050   ** Compute the revised record entries for indices as we go.
2051   **
2052   ** This loop also handles the case of the PRIMARY KEY index for a
2053   ** WITHOUT ROWID table.
2054   */
2055   for(pIdx = indexIteratorFirst(&sIdxIter, &ix);
2056       pIdx;
2057       pIdx = indexIteratorNext(&sIdxIter, &ix)
2058   ){
2059     int regIdx;          /* Range of registers hold conent for pIdx */
2060     int regR;            /* Range of registers holding conflicting PK */
2061     int iThisCur;        /* Cursor for this UNIQUE index */
2062     int addrUniqueOk;    /* Jump here if the UNIQUE constraint is satisfied */
2063     int addrConflictCk;  /* First opcode in the conflict check logic */
2064 
2065     if( aRegIdx[ix]==0 ) continue;  /* Skip indices that do not change */
2066     if( pUpsert ){
2067       pUpsertClause = sqlite3UpsertOfIndex(pUpsert, pIdx);
2068       if( upsertIpkDelay && pUpsertClause==pUpsert ){
2069         sqlite3VdbeJumpHere(v, upsertIpkDelay);
2070       }
2071     }
2072     addrUniqueOk = sqlite3VdbeMakeLabel(pParse);
2073     if( bAffinityDone==0 ){
2074       sqlite3TableAffinity(v, pTab, regNewData+1);
2075       bAffinityDone = 1;
2076     }
2077     VdbeNoopComment((v, "prep index %s", pIdx->zName));
2078     iThisCur = iIdxCur+ix;
2079 
2080 
2081     /* Skip partial indices for which the WHERE clause is not true */
2082     if( pIdx->pPartIdxWhere ){
2083       sqlite3VdbeAddOp2(v, OP_Null, 0, aRegIdx[ix]);
2084       pParse->iSelfTab = -(regNewData+1);
2085       sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, addrUniqueOk,
2086                             SQLITE_JUMPIFNULL);
2087       pParse->iSelfTab = 0;
2088     }
2089 
2090     /* Create a record for this index entry as it should appear after
2091     ** the insert or update.  Store that record in the aRegIdx[ix] register
2092     */
2093     regIdx = aRegIdx[ix]+1;
2094     for(i=0; i<pIdx->nColumn; i++){
2095       int iField = pIdx->aiColumn[i];
2096       int x;
2097       if( iField==XN_EXPR ){
2098         pParse->iSelfTab = -(regNewData+1);
2099         sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[i].pExpr, regIdx+i);
2100         pParse->iSelfTab = 0;
2101         VdbeComment((v, "%s column %d", pIdx->zName, i));
2102       }else if( iField==XN_ROWID || iField==pTab->iPKey ){
2103         x = regNewData;
2104         sqlite3VdbeAddOp2(v, OP_IntCopy, x, regIdx+i);
2105         VdbeComment((v, "rowid"));
2106       }else{
2107         testcase( sqlite3TableColumnToStorage(pTab, iField)!=iField );
2108         x = sqlite3TableColumnToStorage(pTab, iField) + regNewData + 1;
2109         sqlite3VdbeAddOp2(v, OP_SCopy, x, regIdx+i);
2110         VdbeComment((v, "%s", pTab->aCol[iField].zName));
2111       }
2112     }
2113     sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn, aRegIdx[ix]);
2114     VdbeComment((v, "for %s", pIdx->zName));
2115 #ifdef SQLITE_ENABLE_NULL_TRIM
2116     if( pIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){
2117       sqlite3SetMakeRecordP5(v, pIdx->pTable);
2118     }
2119 #endif
2120     sqlite3VdbeReleaseRegisters(pParse, regIdx, pIdx->nColumn, 0, 0);
2121 
2122     /* In an UPDATE operation, if this index is the PRIMARY KEY index
2123     ** of a WITHOUT ROWID table and there has been no change the
2124     ** primary key, then no collision is possible.  The collision detection
2125     ** logic below can all be skipped. */
2126     if( isUpdate && pPk==pIdx && pkChng==0 ){
2127       sqlite3VdbeResolveLabel(v, addrUniqueOk);
2128       continue;
2129     }
2130 
2131     /* Find out what action to take in case there is a uniqueness conflict */
2132     onError = pIdx->onError;
2133     if( onError==OE_None ){
2134       sqlite3VdbeResolveLabel(v, addrUniqueOk);
2135       continue;  /* pIdx is not a UNIQUE index */
2136     }
2137     if( overrideError!=OE_Default ){
2138       onError = overrideError;
2139     }else if( onError==OE_Default ){
2140       onError = OE_Abort;
2141     }
2142 
2143     /* Figure out if the upsert clause applies to this index */
2144     if( pUpsertClause ){
2145       if( pUpsertClause->isDoUpdate==0 ){
2146         onError = OE_Ignore;  /* DO NOTHING is the same as INSERT OR IGNORE */
2147       }else{
2148         onError = OE_Update;  /* DO UPDATE */
2149       }
2150     }
2151 
2152     /* Collision detection may be omitted if all of the following are true:
2153     **   (1) The conflict resolution algorithm is REPLACE
2154     **   (2) The table is a WITHOUT ROWID table
2155     **   (3) There are no secondary indexes on the table
2156     **   (4) No delete triggers need to be fired if there is a conflict
2157     **   (5) No FK constraint counters need to be updated if a conflict occurs.
2158     **
2159     ** This is not possible for ENABLE_PREUPDATE_HOOK builds, as the row
2160     ** must be explicitly deleted in order to ensure any pre-update hook
2161     ** is invoked.  */
2162 #ifndef SQLITE_ENABLE_PREUPDATE_HOOK
2163     if( (ix==0 && pIdx->pNext==0)                   /* Condition 3 */
2164      && pPk==pIdx                                   /* Condition 2 */
2165      && onError==OE_Replace                         /* Condition 1 */
2166      && ( 0==(db->flags&SQLITE_RecTriggers) ||      /* Condition 4 */
2167           0==sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0))
2168      && ( 0==(db->flags&SQLITE_ForeignKeys) ||      /* Condition 5 */
2169          (0==pTab->pFKey && 0==sqlite3FkReferences(pTab)))
2170     ){
2171       sqlite3VdbeResolveLabel(v, addrUniqueOk);
2172       continue;
2173     }
2174 #endif /* ifndef SQLITE_ENABLE_PREUPDATE_HOOK */
2175 
2176     /* Check to see if the new index entry will be unique */
2177     sqlite3VdbeVerifyAbortable(v, onError);
2178     addrConflictCk =
2179       sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk,
2180                            regIdx, pIdx->nKeyCol); VdbeCoverage(v);
2181 
2182     /* Generate code to handle collisions */
2183     regR = pIdx==pPk ? regIdx : sqlite3GetTempRange(pParse, nPkField);
2184     if( isUpdate || onError==OE_Replace ){
2185       if( HasRowid(pTab) ){
2186         sqlite3VdbeAddOp2(v, OP_IdxRowid, iThisCur, regR);
2187         /* Conflict only if the rowid of the existing index entry
2188         ** is different from old-rowid */
2189         if( isUpdate ){
2190           sqlite3VdbeAddOp3(v, OP_Eq, regR, addrUniqueOk, regOldData);
2191           sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
2192           VdbeCoverage(v);
2193         }
2194       }else{
2195         int x;
2196         /* Extract the PRIMARY KEY from the end of the index entry and
2197         ** store it in registers regR..regR+nPk-1 */
2198         if( pIdx!=pPk ){
2199           for(i=0; i<pPk->nKeyCol; i++){
2200             assert( pPk->aiColumn[i]>=0 );
2201             x = sqlite3TableColumnToIndex(pIdx, pPk->aiColumn[i]);
2202             sqlite3VdbeAddOp3(v, OP_Column, iThisCur, x, regR+i);
2203             VdbeComment((v, "%s.%s", pTab->zName,
2204                          pTab->aCol[pPk->aiColumn[i]].zName));
2205           }
2206         }
2207         if( isUpdate ){
2208           /* If currently processing the PRIMARY KEY of a WITHOUT ROWID
2209           ** table, only conflict if the new PRIMARY KEY values are actually
2210           ** different from the old.
2211           **
2212           ** For a UNIQUE index, only conflict if the PRIMARY KEY values
2213           ** of the matched index row are different from the original PRIMARY
2214           ** KEY values of this row before the update.  */
2215           int addrJump = sqlite3VdbeCurrentAddr(v)+pPk->nKeyCol;
2216           int op = OP_Ne;
2217           int regCmp = (IsPrimaryKeyIndex(pIdx) ? regIdx : regR);
2218 
2219           for(i=0; i<pPk->nKeyCol; i++){
2220             char *p4 = (char*)sqlite3LocateCollSeq(pParse, pPk->azColl[i]);
2221             x = pPk->aiColumn[i];
2222             assert( x>=0 );
2223             if( i==(pPk->nKeyCol-1) ){
2224               addrJump = addrUniqueOk;
2225               op = OP_Eq;
2226             }
2227             x = sqlite3TableColumnToStorage(pTab, x);
2228             sqlite3VdbeAddOp4(v, op,
2229                 regOldData+1+x, addrJump, regCmp+i, p4, P4_COLLSEQ
2230             );
2231             sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
2232             VdbeCoverageIf(v, op==OP_Eq);
2233             VdbeCoverageIf(v, op==OP_Ne);
2234           }
2235         }
2236       }
2237     }
2238 
2239     /* Generate code that executes if the new index entry is not unique */
2240     assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
2241         || onError==OE_Ignore || onError==OE_Replace || onError==OE_Update );
2242     switch( onError ){
2243       case OE_Rollback:
2244       case OE_Abort:
2245       case OE_Fail: {
2246         testcase( onError==OE_Rollback );
2247         testcase( onError==OE_Abort );
2248         testcase( onError==OE_Fail );
2249         sqlite3UniqueConstraint(pParse, onError, pIdx);
2250         break;
2251       }
2252 #ifndef SQLITE_OMIT_UPSERT
2253       case OE_Update: {
2254         sqlite3UpsertDoUpdate(pParse, pUpsert, pTab, pIdx, iIdxCur+ix);
2255         /* no break */ deliberate_fall_through
2256       }
2257 #endif
2258       case OE_Ignore: {
2259         testcase( onError==OE_Ignore );
2260         sqlite3VdbeGoto(v, ignoreDest);
2261         break;
2262       }
2263       default: {
2264         int nConflictCk;   /* Number of opcodes in conflict check logic */
2265 
2266         assert( onError==OE_Replace );
2267         nConflictCk = sqlite3VdbeCurrentAddr(v) - addrConflictCk;
2268         assert( nConflictCk>0 );
2269         testcase( nConflictCk>1 );
2270         if( regTrigCnt ){
2271           sqlite3MultiWrite(pParse);
2272           nReplaceTrig++;
2273         }
2274         if( pTrigger && isUpdate ){
2275           sqlite3VdbeAddOp1(v, OP_CursorLock, iDataCur);
2276         }
2277         sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
2278             regR, nPkField, 0, OE_Replace,
2279             (pIdx==pPk ? ONEPASS_SINGLE : ONEPASS_OFF), iThisCur);
2280         if( pTrigger && isUpdate ){
2281           sqlite3VdbeAddOp1(v, OP_CursorUnlock, iDataCur);
2282         }
2283         if( regTrigCnt ){
2284           int addrBypass;  /* Jump destination to bypass recheck logic */
2285 
2286           sqlite3VdbeAddOp2(v, OP_AddImm, regTrigCnt, 1); /* incr trigger cnt */
2287           addrBypass = sqlite3VdbeAddOp0(v, OP_Goto);  /* Bypass recheck */
2288           VdbeComment((v, "bypass recheck"));
2289 
2290           /* Here we insert code that will be invoked after all constraint
2291           ** checks have run, if and only if one or more replace triggers
2292           ** fired. */
2293           sqlite3VdbeResolveLabel(v, lblRecheckOk);
2294           lblRecheckOk = sqlite3VdbeMakeLabel(pParse);
2295           if( pIdx->pPartIdxWhere ){
2296             /* Bypass the recheck if this partial index is not defined
2297             ** for the current row */
2298             sqlite3VdbeAddOp2(v, OP_IsNull, regIdx-1, lblRecheckOk);
2299             VdbeCoverage(v);
2300           }
2301           /* Copy the constraint check code from above, except change
2302           ** the constraint-ok jump destination to be the address of
2303           ** the next retest block */
2304           while( nConflictCk>0 ){
2305             VdbeOp x;    /* Conflict check opcode to copy */
2306             /* The sqlite3VdbeAddOp4() call might reallocate the opcode array.
2307             ** Hence, make a complete copy of the opcode, rather than using
2308             ** a pointer to the opcode. */
2309             x = *sqlite3VdbeGetOp(v, addrConflictCk);
2310             if( x.opcode!=OP_IdxRowid ){
2311               int p2;      /* New P2 value for copied conflict check opcode */
2312               const char *zP4;
2313               if( sqlite3OpcodeProperty[x.opcode]&OPFLG_JUMP ){
2314                 p2 = lblRecheckOk;
2315               }else{
2316                 p2 = x.p2;
2317               }
2318               zP4 = x.p4type==P4_INT32 ? SQLITE_INT_TO_PTR(x.p4.i) : x.p4.z;
2319               sqlite3VdbeAddOp4(v, x.opcode, x.p1, p2, x.p3, zP4, x.p4type);
2320               sqlite3VdbeChangeP5(v, x.p5);
2321               VdbeCoverageIf(v, p2!=x.p2);
2322             }
2323             nConflictCk--;
2324             addrConflictCk++;
2325           }
2326           /* If the retest fails, issue an abort */
2327           sqlite3UniqueConstraint(pParse, OE_Abort, pIdx);
2328 
2329           sqlite3VdbeJumpHere(v, addrBypass); /* Terminate the recheck bypass */
2330         }
2331         seenReplace = 1;
2332         break;
2333       }
2334     }
2335     sqlite3VdbeResolveLabel(v, addrUniqueOk);
2336     if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField);
2337     if( pUpsertClause
2338      && upsertIpkReturn
2339      && sqlite3UpsertNextIsIPK(pUpsertClause)
2340     ){
2341       sqlite3VdbeGoto(v, upsertIpkDelay+1);
2342       sqlite3VdbeJumpHere(v, upsertIpkReturn);
2343       upsertIpkReturn = 0;
2344     }
2345   }
2346 
2347   /* If the IPK constraint is a REPLACE, run it last */
2348   if( ipkTop ){
2349     sqlite3VdbeGoto(v, ipkTop);
2350     VdbeComment((v, "Do IPK REPLACE"));
2351     sqlite3VdbeJumpHere(v, ipkBottom);
2352   }
2353 
2354   /* Recheck all uniqueness constraints after replace triggers have run */
2355   testcase( regTrigCnt!=0 && nReplaceTrig==0 );
2356   assert( regTrigCnt!=0 || nReplaceTrig==0 );
2357   if( nReplaceTrig ){
2358     sqlite3VdbeAddOp2(v, OP_IfNot, regTrigCnt, lblRecheckOk);VdbeCoverage(v);
2359     if( !pPk ){
2360       if( isUpdate ){
2361         sqlite3VdbeAddOp3(v, OP_Eq, regNewData, addrRecheck, regOldData);
2362         sqlite3VdbeChangeP5(v, SQLITE_NOTNULL);
2363         VdbeCoverage(v);
2364       }
2365       sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRecheck, regNewData);
2366       VdbeCoverage(v);
2367       sqlite3RowidConstraint(pParse, OE_Abort, pTab);
2368     }else{
2369       sqlite3VdbeGoto(v, addrRecheck);
2370     }
2371     sqlite3VdbeResolveLabel(v, lblRecheckOk);
2372   }
2373 
2374   /* Generate the table record */
2375   if( HasRowid(pTab) ){
2376     int regRec = aRegIdx[ix];
2377     sqlite3VdbeAddOp3(v, OP_MakeRecord, regNewData+1, pTab->nNVCol, regRec);
2378     sqlite3SetMakeRecordP5(v, pTab);
2379     if( !bAffinityDone ){
2380       sqlite3TableAffinity(v, pTab, 0);
2381     }
2382   }
2383 
2384   *pbMayReplace = seenReplace;
2385   VdbeModuleComment((v, "END: GenCnstCks(%d)", seenReplace));
2386 }
2387 
2388 #ifdef SQLITE_ENABLE_NULL_TRIM
2389 /*
2390 ** Change the P5 operand on the last opcode (which should be an OP_MakeRecord)
2391 ** to be the number of columns in table pTab that must not be NULL-trimmed.
2392 **
2393 ** Or if no columns of pTab may be NULL-trimmed, leave P5 at zero.
2394 */
2395 void sqlite3SetMakeRecordP5(Vdbe *v, Table *pTab){
2396   u16 i;
2397 
2398   /* Records with omitted columns are only allowed for schema format
2399   ** version 2 and later (SQLite version 3.1.4, 2005-02-20). */
2400   if( pTab->pSchema->file_format<2 ) return;
2401 
2402   for(i=pTab->nCol-1; i>0; i--){
2403     if( pTab->aCol[i].pDflt!=0 ) break;
2404     if( pTab->aCol[i].colFlags & COLFLAG_PRIMKEY ) break;
2405   }
2406   sqlite3VdbeChangeP5(v, i+1);
2407 }
2408 #endif
2409 
2410 /*
2411 ** This routine generates code to finish the INSERT or UPDATE operation
2412 ** that was started by a prior call to sqlite3GenerateConstraintChecks.
2413 ** A consecutive range of registers starting at regNewData contains the
2414 ** rowid and the content to be inserted.
2415 **
2416 ** The arguments to this routine should be the same as the first six
2417 ** arguments to sqlite3GenerateConstraintChecks.
2418 */
2419 void sqlite3CompleteInsertion(
2420   Parse *pParse,      /* The parser context */
2421   Table *pTab,        /* the table into which we are inserting */
2422   int iDataCur,       /* Cursor of the canonical data source */
2423   int iIdxCur,        /* First index cursor */
2424   int regNewData,     /* Range of content */
2425   int *aRegIdx,       /* Register used by each index.  0 for unused indices */
2426   int update_flags,   /* True for UPDATE, False for INSERT */
2427   int appendBias,     /* True if this is likely to be an append */
2428   int useSeekResult   /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */
2429 ){
2430   Vdbe *v;            /* Prepared statements under construction */
2431   Index *pIdx;        /* An index being inserted or updated */
2432   u8 pik_flags;       /* flag values passed to the btree insert */
2433   int i;              /* Loop counter */
2434 
2435   assert( update_flags==0
2436        || update_flags==OPFLAG_ISUPDATE
2437        || update_flags==(OPFLAG_ISUPDATE|OPFLAG_SAVEPOSITION)
2438   );
2439 
2440   v = pParse->pVdbe;
2441   assert( v!=0 );
2442   assert( pTab->pSelect==0 );  /* This table is not a VIEW */
2443   for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
2444     /* All REPLACE indexes are at the end of the list */
2445     assert( pIdx->onError!=OE_Replace
2446          || pIdx->pNext==0
2447          || pIdx->pNext->onError==OE_Replace );
2448     if( aRegIdx[i]==0 ) continue;
2449     if( pIdx->pPartIdxWhere ){
2450       sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2);
2451       VdbeCoverage(v);
2452     }
2453     pik_flags = (useSeekResult ? OPFLAG_USESEEKRESULT : 0);
2454     if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
2455       assert( pParse->nested==0 );
2456       pik_flags |= OPFLAG_NCHANGE;
2457       pik_flags |= (update_flags & OPFLAG_SAVEPOSITION);
2458 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
2459       if( update_flags==0 ){
2460         int r = sqlite3GetTempReg(pParse);
2461         sqlite3VdbeAddOp2(v, OP_Integer, 0, r);
2462         sqlite3VdbeAddOp4(v, OP_Insert,
2463             iIdxCur+i, aRegIdx[i], r, (char*)pTab, P4_TABLE
2464         );
2465         sqlite3VdbeChangeP5(v, OPFLAG_ISNOOP);
2466         sqlite3ReleaseTempReg(pParse, r);
2467       }
2468 #endif
2469     }
2470     sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i],
2471                          aRegIdx[i]+1,
2472                          pIdx->uniqNotNull ? pIdx->nKeyCol: pIdx->nColumn);
2473     sqlite3VdbeChangeP5(v, pik_flags);
2474   }
2475   if( !HasRowid(pTab) ) return;
2476   if( pParse->nested ){
2477     pik_flags = 0;
2478   }else{
2479     pik_flags = OPFLAG_NCHANGE;
2480     pik_flags |= (update_flags?update_flags:OPFLAG_LASTROWID);
2481   }
2482   if( appendBias ){
2483     pik_flags |= OPFLAG_APPEND;
2484   }
2485   if( useSeekResult ){
2486     pik_flags |= OPFLAG_USESEEKRESULT;
2487   }
2488   sqlite3VdbeAddOp3(v, OP_Insert, iDataCur, aRegIdx[i], regNewData);
2489   if( !pParse->nested ){
2490     sqlite3VdbeAppendP4(v, pTab, P4_TABLE);
2491   }
2492   sqlite3VdbeChangeP5(v, pik_flags);
2493 }
2494 
2495 /*
2496 ** Allocate cursors for the pTab table and all its indices and generate
2497 ** code to open and initialized those cursors.
2498 **
2499 ** The cursor for the object that contains the complete data (normally
2500 ** the table itself, but the PRIMARY KEY index in the case of a WITHOUT
2501 ** ROWID table) is returned in *piDataCur.  The first index cursor is
2502 ** returned in *piIdxCur.  The number of indices is returned.
2503 **
2504 ** Use iBase as the first cursor (either the *piDataCur for rowid tables
2505 ** or the first index for WITHOUT ROWID tables) if it is non-negative.
2506 ** If iBase is negative, then allocate the next available cursor.
2507 **
2508 ** For a rowid table, *piDataCur will be exactly one less than *piIdxCur.
2509 ** For a WITHOUT ROWID table, *piDataCur will be somewhere in the range
2510 ** of *piIdxCurs, depending on where the PRIMARY KEY index appears on the
2511 ** pTab->pIndex list.
2512 **
2513 ** If pTab is a virtual table, then this routine is a no-op and the
2514 ** *piDataCur and *piIdxCur values are left uninitialized.
2515 */
2516 int sqlite3OpenTableAndIndices(
2517   Parse *pParse,   /* Parsing context */
2518   Table *pTab,     /* Table to be opened */
2519   int op,          /* OP_OpenRead or OP_OpenWrite */
2520   u8 p5,           /* P5 value for OP_Open* opcodes (except on WITHOUT ROWID) */
2521   int iBase,       /* Use this for the table cursor, if there is one */
2522   u8 *aToOpen,     /* If not NULL: boolean for each table and index */
2523   int *piDataCur,  /* Write the database source cursor number here */
2524   int *piIdxCur    /* Write the first index cursor number here */
2525 ){
2526   int i;
2527   int iDb;
2528   int iDataCur;
2529   Index *pIdx;
2530   Vdbe *v;
2531 
2532   assert( op==OP_OpenRead || op==OP_OpenWrite );
2533   assert( op==OP_OpenWrite || p5==0 );
2534   if( IsVirtual(pTab) ){
2535     /* This routine is a no-op for virtual tables. Leave the output
2536     ** variables *piDataCur and *piIdxCur uninitialized so that valgrind
2537     ** can detect if they are used by mistake in the caller. */
2538     return 0;
2539   }
2540   iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
2541   v = pParse->pVdbe;
2542   assert( v!=0 );
2543   if( iBase<0 ) iBase = pParse->nTab;
2544   iDataCur = iBase++;
2545   if( piDataCur ) *piDataCur = iDataCur;
2546   if( HasRowid(pTab) && (aToOpen==0 || aToOpen[0]) ){
2547     sqlite3OpenTable(pParse, iDataCur, iDb, pTab, op);
2548   }else{
2549     sqlite3TableLock(pParse, iDb, pTab->tnum, op==OP_OpenWrite, pTab->zName);
2550   }
2551   if( piIdxCur ) *piIdxCur = iBase;
2552   for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
2553     int iIdxCur = iBase++;
2554     assert( pIdx->pSchema==pTab->pSchema );
2555     if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){
2556       if( piDataCur ) *piDataCur = iIdxCur;
2557       p5 = 0;
2558     }
2559     if( aToOpen==0 || aToOpen[i+1] ){
2560       sqlite3VdbeAddOp3(v, op, iIdxCur, pIdx->tnum, iDb);
2561       sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
2562       sqlite3VdbeChangeP5(v, p5);
2563       VdbeComment((v, "%s", pIdx->zName));
2564     }
2565   }
2566   if( iBase>pParse->nTab ) pParse->nTab = iBase;
2567   return i;
2568 }
2569 
2570 
2571 #ifdef SQLITE_TEST
2572 /*
2573 ** The following global variable is incremented whenever the
2574 ** transfer optimization is used.  This is used for testing
2575 ** purposes only - to make sure the transfer optimization really
2576 ** is happening when it is supposed to.
2577 */
2578 int sqlite3_xferopt_count;
2579 #endif /* SQLITE_TEST */
2580 
2581 
2582 #ifndef SQLITE_OMIT_XFER_OPT
2583 /*
2584 ** Check to see if index pSrc is compatible as a source of data
2585 ** for index pDest in an insert transfer optimization.  The rules
2586 ** for a compatible index:
2587 **
2588 **    *   The index is over the same set of columns
2589 **    *   The same DESC and ASC markings occurs on all columns
2590 **    *   The same onError processing (OE_Abort, OE_Ignore, etc)
2591 **    *   The same collating sequence on each column
2592 **    *   The index has the exact same WHERE clause
2593 */
2594 static int xferCompatibleIndex(Index *pDest, Index *pSrc){
2595   int i;
2596   assert( pDest && pSrc );
2597   assert( pDest->pTable!=pSrc->pTable );
2598   if( pDest->nKeyCol!=pSrc->nKeyCol || pDest->nColumn!=pSrc->nColumn ){
2599     return 0;   /* Different number of columns */
2600   }
2601   if( pDest->onError!=pSrc->onError ){
2602     return 0;   /* Different conflict resolution strategies */
2603   }
2604   for(i=0; i<pSrc->nKeyCol; i++){
2605     if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){
2606       return 0;   /* Different columns indexed */
2607     }
2608     if( pSrc->aiColumn[i]==XN_EXPR ){
2609       assert( pSrc->aColExpr!=0 && pDest->aColExpr!=0 );
2610       if( sqlite3ExprCompare(0, pSrc->aColExpr->a[i].pExpr,
2611                              pDest->aColExpr->a[i].pExpr, -1)!=0 ){
2612         return 0;   /* Different expressions in the index */
2613       }
2614     }
2615     if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){
2616       return 0;   /* Different sort orders */
2617     }
2618     if( sqlite3_stricmp(pSrc->azColl[i],pDest->azColl[i])!=0 ){
2619       return 0;   /* Different collating sequences */
2620     }
2621   }
2622   if( sqlite3ExprCompare(0, pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1) ){
2623     return 0;     /* Different WHERE clauses */
2624   }
2625 
2626   /* If no test above fails then the indices must be compatible */
2627   return 1;
2628 }
2629 
2630 /*
2631 ** Attempt the transfer optimization on INSERTs of the form
2632 **
2633 **     INSERT INTO tab1 SELECT * FROM tab2;
2634 **
2635 ** The xfer optimization transfers raw records from tab2 over to tab1.
2636 ** Columns are not decoded and reassembled, which greatly improves
2637 ** performance.  Raw index records are transferred in the same way.
2638 **
2639 ** The xfer optimization is only attempted if tab1 and tab2 are compatible.
2640 ** There are lots of rules for determining compatibility - see comments
2641 ** embedded in the code for details.
2642 **
2643 ** This routine returns TRUE if the optimization is guaranteed to be used.
2644 ** Sometimes the xfer optimization will only work if the destination table
2645 ** is empty - a factor that can only be determined at run-time.  In that
2646 ** case, this routine generates code for the xfer optimization but also
2647 ** does a test to see if the destination table is empty and jumps over the
2648 ** xfer optimization code if the test fails.  In that case, this routine
2649 ** returns FALSE so that the caller will know to go ahead and generate
2650 ** an unoptimized transfer.  This routine also returns FALSE if there
2651 ** is no chance that the xfer optimization can be applied.
2652 **
2653 ** This optimization is particularly useful at making VACUUM run faster.
2654 */
2655 static int xferOptimization(
2656   Parse *pParse,        /* Parser context */
2657   Table *pDest,         /* The table we are inserting into */
2658   Select *pSelect,      /* A SELECT statement to use as the data source */
2659   int onError,          /* How to handle constraint errors */
2660   int iDbDest           /* The database of pDest */
2661 ){
2662   sqlite3 *db = pParse->db;
2663   ExprList *pEList;                /* The result set of the SELECT */
2664   Table *pSrc;                     /* The table in the FROM clause of SELECT */
2665   Index *pSrcIdx, *pDestIdx;       /* Source and destination indices */
2666   struct SrcList_item *pItem;      /* An element of pSelect->pSrc */
2667   int i;                           /* Loop counter */
2668   int iDbSrc;                      /* The database of pSrc */
2669   int iSrc, iDest;                 /* Cursors from source and destination */
2670   int addr1, addr2;                /* Loop addresses */
2671   int emptyDestTest = 0;           /* Address of test for empty pDest */
2672   int emptySrcTest = 0;            /* Address of test for empty pSrc */
2673   Vdbe *v;                         /* The VDBE we are building */
2674   int regAutoinc;                  /* Memory register used by AUTOINC */
2675   int destHasUniqueIdx = 0;        /* True if pDest has a UNIQUE index */
2676   int regData, regRowid;           /* Registers holding data and rowid */
2677 
2678   if( pSelect==0 ){
2679     return 0;   /* Must be of the form  INSERT INTO ... SELECT ... */
2680   }
2681   if( pParse->pWith || pSelect->pWith ){
2682     /* Do not attempt to process this query if there are an WITH clauses
2683     ** attached to it. Proceeding may generate a false "no such table: xxx"
2684     ** error if pSelect reads from a CTE named "xxx".  */
2685     return 0;
2686   }
2687   if( sqlite3TriggerList(pParse, pDest) ){
2688     return 0;   /* tab1 must not have triggers */
2689   }
2690 #ifndef SQLITE_OMIT_VIRTUALTABLE
2691   if( IsVirtual(pDest) ){
2692     return 0;   /* tab1 must not be a virtual table */
2693   }
2694 #endif
2695   if( onError==OE_Default ){
2696     if( pDest->iPKey>=0 ) onError = pDest->keyConf;
2697     if( onError==OE_Default ) onError = OE_Abort;
2698   }
2699   assert(pSelect->pSrc);   /* allocated even if there is no FROM clause */
2700   if( pSelect->pSrc->nSrc!=1 ){
2701     return 0;   /* FROM clause must have exactly one term */
2702   }
2703   if( pSelect->pSrc->a[0].pSelect ){
2704     return 0;   /* FROM clause cannot contain a subquery */
2705   }
2706   if( pSelect->pWhere ){
2707     return 0;   /* SELECT may not have a WHERE clause */
2708   }
2709   if( pSelect->pOrderBy ){
2710     return 0;   /* SELECT may not have an ORDER BY clause */
2711   }
2712   /* Do not need to test for a HAVING clause.  If HAVING is present but
2713   ** there is no ORDER BY, we will get an error. */
2714   if( pSelect->pGroupBy ){
2715     return 0;   /* SELECT may not have a GROUP BY clause */
2716   }
2717   if( pSelect->pLimit ){
2718     return 0;   /* SELECT may not have a LIMIT clause */
2719   }
2720   if( pSelect->pPrior ){
2721     return 0;   /* SELECT may not be a compound query */
2722   }
2723   if( pSelect->selFlags & SF_Distinct ){
2724     return 0;   /* SELECT may not be DISTINCT */
2725   }
2726   pEList = pSelect->pEList;
2727   assert( pEList!=0 );
2728   if( pEList->nExpr!=1 ){
2729     return 0;   /* The result set must have exactly one column */
2730   }
2731   assert( pEList->a[0].pExpr );
2732   if( pEList->a[0].pExpr->op!=TK_ASTERISK ){
2733     return 0;   /* The result set must be the special operator "*" */
2734   }
2735 
2736   /* At this point we have established that the statement is of the
2737   ** correct syntactic form to participate in this optimization.  Now
2738   ** we have to check the semantics.
2739   */
2740   pItem = pSelect->pSrc->a;
2741   pSrc = sqlite3LocateTableItem(pParse, 0, pItem);
2742   if( pSrc==0 ){
2743     return 0;   /* FROM clause does not contain a real table */
2744   }
2745   if( pSrc->tnum==pDest->tnum && pSrc->pSchema==pDest->pSchema ){
2746     testcase( pSrc!=pDest ); /* Possible due to bad sqlite_schema.rootpage */
2747     return 0;   /* tab1 and tab2 may not be the same table */
2748   }
2749   if( HasRowid(pDest)!=HasRowid(pSrc) ){
2750     return 0;   /* source and destination must both be WITHOUT ROWID or not */
2751   }
2752 #ifndef SQLITE_OMIT_VIRTUALTABLE
2753   if( IsVirtual(pSrc) ){
2754     return 0;   /* tab2 must not be a virtual table */
2755   }
2756 #endif
2757   if( pSrc->pSelect ){
2758     return 0;   /* tab2 may not be a view */
2759   }
2760   if( pDest->nCol!=pSrc->nCol ){
2761     return 0;   /* Number of columns must be the same in tab1 and tab2 */
2762   }
2763   if( pDest->iPKey!=pSrc->iPKey ){
2764     return 0;   /* Both tables must have the same INTEGER PRIMARY KEY */
2765   }
2766   for(i=0; i<pDest->nCol; i++){
2767     Column *pDestCol = &pDest->aCol[i];
2768     Column *pSrcCol = &pSrc->aCol[i];
2769 #ifdef SQLITE_ENABLE_HIDDEN_COLUMNS
2770     if( (db->mDbFlags & DBFLAG_Vacuum)==0
2771      && (pDestCol->colFlags | pSrcCol->colFlags) & COLFLAG_HIDDEN
2772     ){
2773       return 0;    /* Neither table may have __hidden__ columns */
2774     }
2775 #endif
2776 #ifndef SQLITE_OMIT_GENERATED_COLUMNS
2777     /* Even if tables t1 and t2 have identical schemas, if they contain
2778     ** generated columns, then this statement is semantically incorrect:
2779     **
2780     **     INSERT INTO t2 SELECT * FROM t1;
2781     **
2782     ** The reason is that generated column values are returned by the
2783     ** the SELECT statement on the right but the INSERT statement on the
2784     ** left wants them to be omitted.
2785     **
2786     ** Nevertheless, this is a useful notational shorthand to tell SQLite
2787     ** to do a bulk transfer all of the content from t1 over to t2.
2788     **
2789     ** We could, in theory, disable this (except for internal use by the
2790     ** VACUUM command where it is actually needed).  But why do that?  It
2791     ** seems harmless enough, and provides a useful service.
2792     */
2793     if( (pDestCol->colFlags & COLFLAG_GENERATED) !=
2794         (pSrcCol->colFlags & COLFLAG_GENERATED) ){
2795       return 0;    /* Both columns have the same generated-column type */
2796     }
2797     /* But the transfer is only allowed if both the source and destination
2798     ** tables have the exact same expressions for generated columns.
2799     ** This requirement could be relaxed for VIRTUAL columns, I suppose.
2800     */
2801     if( (pDestCol->colFlags & COLFLAG_GENERATED)!=0 ){
2802       if( sqlite3ExprCompare(0, pSrcCol->pDflt, pDestCol->pDflt, -1)!=0 ){
2803         testcase( pDestCol->colFlags & COLFLAG_VIRTUAL );
2804         testcase( pDestCol->colFlags & COLFLAG_STORED );
2805         return 0;  /* Different generator expressions */
2806       }
2807     }
2808 #endif
2809     if( pDestCol->affinity!=pSrcCol->affinity ){
2810       return 0;    /* Affinity must be the same on all columns */
2811     }
2812     if( sqlite3_stricmp(pDestCol->zColl, pSrcCol->zColl)!=0 ){
2813       return 0;    /* Collating sequence must be the same on all columns */
2814     }
2815     if( pDestCol->notNull && !pSrcCol->notNull ){
2816       return 0;    /* tab2 must be NOT NULL if tab1 is */
2817     }
2818     /* Default values for second and subsequent columns need to match. */
2819     if( (pDestCol->colFlags & COLFLAG_GENERATED)==0 && i>0 ){
2820       assert( pDestCol->pDflt==0 || pDestCol->pDflt->op==TK_SPAN );
2821       assert( pSrcCol->pDflt==0 || pSrcCol->pDflt->op==TK_SPAN );
2822       if( (pDestCol->pDflt==0)!=(pSrcCol->pDflt==0)
2823        || (pDestCol->pDflt && strcmp(pDestCol->pDflt->u.zToken,
2824                                        pSrcCol->pDflt->u.zToken)!=0)
2825       ){
2826         return 0;    /* Default values must be the same for all columns */
2827       }
2828     }
2829   }
2830   for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
2831     if( IsUniqueIndex(pDestIdx) ){
2832       destHasUniqueIdx = 1;
2833     }
2834     for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){
2835       if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
2836     }
2837     if( pSrcIdx==0 ){
2838       return 0;    /* pDestIdx has no corresponding index in pSrc */
2839     }
2840     if( pSrcIdx->tnum==pDestIdx->tnum && pSrc->pSchema==pDest->pSchema
2841          && sqlite3FaultSim(411)==SQLITE_OK ){
2842       /* The sqlite3FaultSim() call allows this corruption test to be
2843       ** bypassed during testing, in order to exercise other corruption tests
2844       ** further downstream. */
2845       return 0;   /* Corrupt schema - two indexes on the same btree */
2846     }
2847   }
2848 #ifndef SQLITE_OMIT_CHECK
2849   if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){
2850     return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
2851   }
2852 #endif
2853 #ifndef SQLITE_OMIT_FOREIGN_KEY
2854   /* Disallow the transfer optimization if the destination table constains
2855   ** any foreign key constraints.  This is more restrictive than necessary.
2856   ** But the main beneficiary of the transfer optimization is the VACUUM
2857   ** command, and the VACUUM command disables foreign key constraints.  So
2858   ** the extra complication to make this rule less restrictive is probably
2859   ** not worth the effort.  Ticket [6284df89debdfa61db8073e062908af0c9b6118e]
2860   */
2861   if( (db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){
2862     return 0;
2863   }
2864 #endif
2865   if( (db->flags & SQLITE_CountRows)!=0 ){
2866     return 0;  /* xfer opt does not play well with PRAGMA count_changes */
2867   }
2868 
2869   /* If we get this far, it means that the xfer optimization is at
2870   ** least a possibility, though it might only work if the destination
2871   ** table (tab1) is initially empty.
2872   */
2873 #ifdef SQLITE_TEST
2874   sqlite3_xferopt_count++;
2875 #endif
2876   iDbSrc = sqlite3SchemaToIndex(db, pSrc->pSchema);
2877   v = sqlite3GetVdbe(pParse);
2878   sqlite3CodeVerifySchema(pParse, iDbSrc);
2879   iSrc = pParse->nTab++;
2880   iDest = pParse->nTab++;
2881   regAutoinc = autoIncBegin(pParse, iDbDest, pDest);
2882   regData = sqlite3GetTempReg(pParse);
2883   sqlite3VdbeAddOp2(v, OP_Null, 0, regData);
2884   regRowid = sqlite3GetTempReg(pParse);
2885   sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite);
2886   assert( HasRowid(pDest) || destHasUniqueIdx );
2887   if( (db->mDbFlags & DBFLAG_Vacuum)==0 && (
2888       (pDest->iPKey<0 && pDest->pIndex!=0)          /* (1) */
2889    || destHasUniqueIdx                              /* (2) */
2890    || (onError!=OE_Abort && onError!=OE_Rollback)   /* (3) */
2891   )){
2892     /* In some circumstances, we are able to run the xfer optimization
2893     ** only if the destination table is initially empty. Unless the
2894     ** DBFLAG_Vacuum flag is set, this block generates code to make
2895     ** that determination. If DBFLAG_Vacuum is set, then the destination
2896     ** table is always empty.
2897     **
2898     ** Conditions under which the destination must be empty:
2899     **
2900     ** (1) There is no INTEGER PRIMARY KEY but there are indices.
2901     **     (If the destination is not initially empty, the rowid fields
2902     **     of index entries might need to change.)
2903     **
2904     ** (2) The destination has a unique index.  (The xfer optimization
2905     **     is unable to test uniqueness.)
2906     **
2907     ** (3) onError is something other than OE_Abort and OE_Rollback.
2908     */
2909     addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0); VdbeCoverage(v);
2910     emptyDestTest = sqlite3VdbeAddOp0(v, OP_Goto);
2911     sqlite3VdbeJumpHere(v, addr1);
2912   }
2913   if( HasRowid(pSrc) ){
2914     u8 insFlags;
2915     sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead);
2916     emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v);
2917     if( pDest->iPKey>=0 ){
2918       addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
2919       if( (db->mDbFlags & DBFLAG_Vacuum)==0 ){
2920         sqlite3VdbeVerifyAbortable(v, onError);
2921         addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid);
2922         VdbeCoverage(v);
2923         sqlite3RowidConstraint(pParse, onError, pDest);
2924         sqlite3VdbeJumpHere(v, addr2);
2925       }
2926       autoIncStep(pParse, regAutoinc, regRowid);
2927     }else if( pDest->pIndex==0 && !(db->mDbFlags & DBFLAG_VacuumInto) ){
2928       addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid);
2929     }else{
2930       addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
2931       assert( (pDest->tabFlags & TF_Autoincrement)==0 );
2932     }
2933 
2934     if( db->mDbFlags & DBFLAG_Vacuum ){
2935       sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest);
2936       insFlags = OPFLAG_APPEND|OPFLAG_USESEEKRESULT|OPFLAG_PREFORMAT;
2937     }else{
2938       insFlags = OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND|OPFLAG_PREFORMAT;
2939     }
2940 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK
2941     if( db->xPreUpdateCallback ){
2942       sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1);
2943       insFlags &= ~OPFLAG_PREFORMAT;
2944     }else
2945 #endif
2946     {
2947       sqlite3VdbeAddOp3(v, OP_RowCell, iDest, iSrc, regRowid);
2948     }
2949     sqlite3VdbeAddOp4(v, OP_Insert, iDest, regData, regRowid,
2950         (char*)pDest, P4_TABLE);
2951     sqlite3VdbeChangeP5(v, insFlags);
2952 
2953     sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1); VdbeCoverage(v);
2954     sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
2955     sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
2956   }else{
2957     sqlite3TableLock(pParse, iDbDest, pDest->tnum, 1, pDest->zName);
2958     sqlite3TableLock(pParse, iDbSrc, pSrc->tnum, 0, pSrc->zName);
2959   }
2960   for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
2961     u8 idxInsFlags = 0;
2962     for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){
2963       if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
2964     }
2965     assert( pSrcIdx );
2966     sqlite3VdbeAddOp3(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc);
2967     sqlite3VdbeSetP4KeyInfo(pParse, pSrcIdx);
2968     VdbeComment((v, "%s", pSrcIdx->zName));
2969     sqlite3VdbeAddOp3(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest);
2970     sqlite3VdbeSetP4KeyInfo(pParse, pDestIdx);
2971     sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR);
2972     VdbeComment((v, "%s", pDestIdx->zName));
2973     addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v);
2974     if( db->mDbFlags & DBFLAG_Vacuum ){
2975       /* This INSERT command is part of a VACUUM operation, which guarantees
2976       ** that the destination table is empty. If all indexed columns use
2977       ** collation sequence BINARY, then it can also be assumed that the
2978       ** index will be populated by inserting keys in strictly sorted
2979       ** order. In this case, instead of seeking within the b-tree as part
2980       ** of every OP_IdxInsert opcode, an OP_SeekEnd is added before the
2981       ** OP_IdxInsert to seek to the point within the b-tree where each key
2982       ** should be inserted. This is faster.
2983       **
2984       ** If any of the indexed columns use a collation sequence other than
2985       ** BINARY, this optimization is disabled. This is because the user
2986       ** might change the definition of a collation sequence and then run
2987       ** a VACUUM command. In that case keys may not be written in strictly
2988       ** sorted order.  */
2989       for(i=0; i<pSrcIdx->nColumn; i++){
2990         const char *zColl = pSrcIdx->azColl[i];
2991         if( sqlite3_stricmp(sqlite3StrBINARY, zColl) ) break;
2992       }
2993       if( i==pSrcIdx->nColumn ){
2994         idxInsFlags = OPFLAG_USESEEKRESULT|OPFLAG_PREFORMAT;
2995         sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest);
2996         sqlite3VdbeAddOp2(v, OP_RowCell, iDest, iSrc);
2997       }
2998     }else if( !HasRowid(pSrc) && pDestIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){
2999       idxInsFlags |= OPFLAG_NCHANGE;
3000     }
3001     if( idxInsFlags!=(OPFLAG_USESEEKRESULT|OPFLAG_PREFORMAT) ){
3002       sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1);
3003     }
3004     sqlite3VdbeAddOp2(v, OP_IdxInsert, iDest, regData);
3005     sqlite3VdbeChangeP5(v, idxInsFlags|OPFLAG_APPEND);
3006     sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); VdbeCoverage(v);
3007     sqlite3VdbeJumpHere(v, addr1);
3008     sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
3009     sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
3010   }
3011   if( emptySrcTest ) sqlite3VdbeJumpHere(v, emptySrcTest);
3012   sqlite3ReleaseTempReg(pParse, regRowid);
3013   sqlite3ReleaseTempReg(pParse, regData);
3014   if( emptyDestTest ){
3015     sqlite3AutoincrementEnd(pParse);
3016     sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0);
3017     sqlite3VdbeJumpHere(v, emptyDestTest);
3018     sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);
3019     return 0;
3020   }else{
3021     return 1;
3022   }
3023 }
3024 #endif /* SQLITE_OMIT_XFER_OPT */
3025