xref: /sqlite-3.40.0/src/vdbeInt.h (revision e8f2c9dc)
1 /*
2 ** 2003 September 6
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 is the header file for information that is private to the
13 ** VDBE.  This information used to all be at the top of the single
14 ** source code file "vdbe.c".  When that file became too big (over
15 ** 6000 lines long) it was split up into several smaller files and
16 ** this header information was factored out.
17 */
18 #ifndef _VDBEINT_H_
19 #define _VDBEINT_H_
20 
21 /*
22 ** The maximum number of times that a statement will try to reparse
23 ** itself before giving up and returning SQLITE_SCHEMA.
24 */
25 #ifndef SQLITE_MAX_SCHEMA_RETRY
26 # define SQLITE_MAX_SCHEMA_RETRY 50
27 #endif
28 
29 /*
30 ** SQL is translated into a sequence of instructions to be
31 ** executed by a virtual machine.  Each instruction is an instance
32 ** of the following structure.
33 */
34 typedef struct VdbeOp Op;
35 
36 /*
37 ** Boolean values
38 */
39 typedef unsigned Bool;
40 
41 /* Opaque type used by code in vdbesort.c */
42 typedef struct VdbeSorter VdbeSorter;
43 
44 /* Opaque type used by the explainer */
45 typedef struct Explain Explain;
46 
47 /* Elements of the linked list at Vdbe.pAuxData */
48 typedef struct AuxData AuxData;
49 
50 /*
51 ** A cursor is a pointer into a single BTree within a database file.
52 ** The cursor can seek to a BTree entry with a particular key, or
53 ** loop over all entries of the Btree.  You can also insert new BTree
54 ** entries or retrieve the key or data from the entry that the cursor
55 ** is currently pointing to.
56 **
57 ** Cursors can also point to virtual tables, sorters, or "pseudo-tables".
58 ** A pseudo-table is a single-row table implemented by registers.
59 **
60 ** Every cursor that the virtual machine has open is represented by an
61 ** instance of the following structure.
62 */
63 struct VdbeCursor {
64   BtCursor *pCursor;    /* The cursor structure of the backend */
65   Btree *pBt;           /* Separate file holding temporary table */
66   KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
67   int seekResult;       /* Result of previous sqlite3BtreeMoveto() */
68   int pseudoTableReg;   /* Register holding pseudotable content. */
69   i16 nField;           /* Number of fields in the header */
70   u16 nHdrParsed;       /* Number of header fields parsed so far */
71 #ifdef SQLITE_DEBUG
72   u8 seekOp;            /* Most recent seek operation on this cursor */
73 #endif
74   i8 iDb;               /* Index of cursor database in db->aDb[] (or -1) */
75   u8 nullRow;           /* True if pointing to a row with no data */
76   u8 rowidIsValid;      /* True if lastRowid is valid */
77   u8 deferredMoveto;    /* A call to sqlite3BtreeMoveto() is needed */
78   Bool isEphemeral:1;   /* True for an ephemeral table */
79   Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
80   Bool isTable:1;       /* True if a table requiring integer keys */
81   Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */
82   Pgno pgnoRoot;        /* Root page of the open btree cursor */
83   sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
84   i64 seqCount;         /* Sequence counter */
85   i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
86   i64 lastRowid;        /* Rowid being deleted by OP_Delete */
87   VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */
88 
89   /* Cached information about the header for the data record that the
90   ** cursor is currently pointing to.  Only valid if cacheStatus matches
91   ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
92   ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
93   ** the cache is out of date.
94   **
95   ** aRow might point to (ephemeral) data for the current row, or it might
96   ** be NULL.
97   */
98   u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
99   u32 payloadSize;      /* Total number of bytes in the record */
100   u32 szRow;            /* Byte available in aRow */
101   u32 iHdrOffset;       /* Offset to next unparsed byte of the header */
102   const u8 *aRow;       /* Data for the current row, if all on one page */
103   u32 aType[1];         /* Type values for all entries in the record */
104   /* 2*nField extra array elements allocated for aType[], beyond the one
105   ** static element declared in the structure.  nField total array slots for
106   ** aType[] and nField+1 array slots for aOffset[] */
107 };
108 typedef struct VdbeCursor VdbeCursor;
109 
110 /*
111 ** When a sub-program is executed (OP_Program), a structure of this type
112 ** is allocated to store the current value of the program counter, as
113 ** well as the current memory cell array and various other frame specific
114 ** values stored in the Vdbe struct. When the sub-program is finished,
115 ** these values are copied back to the Vdbe from the VdbeFrame structure,
116 ** restoring the state of the VM to as it was before the sub-program
117 ** began executing.
118 **
119 ** The memory for a VdbeFrame object is allocated and managed by a memory
120 ** cell in the parent (calling) frame. When the memory cell is deleted or
121 ** overwritten, the VdbeFrame object is not freed immediately. Instead, it
122 ** is linked into the Vdbe.pDelFrame list. The contents of the Vdbe.pDelFrame
123 ** list is deleted when the VM is reset in VdbeHalt(). The reason for doing
124 ** this instead of deleting the VdbeFrame immediately is to avoid recursive
125 ** calls to sqlite3VdbeMemRelease() when the memory cells belonging to the
126 ** child frame are released.
127 **
128 ** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
129 ** set to NULL if the currently executing frame is the main program.
130 */
131 typedef struct VdbeFrame VdbeFrame;
132 struct VdbeFrame {
133   Vdbe *v;                /* VM this frame belongs to */
134   VdbeFrame *pParent;     /* Parent of this frame, or NULL if parent is main */
135   Op *aOp;                /* Program instructions for parent frame */
136   Mem *aMem;              /* Array of memory cells for parent frame */
137   u8 *aOnceFlag;          /* Array of OP_Once flags for parent frame */
138   VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
139   void *token;            /* Copy of SubProgram.token */
140   i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
141   int nCursor;            /* Number of entries in apCsr */
142   int pc;                 /* Program Counter in parent (calling) frame */
143   int nOp;                /* Size of aOp array */
144   int nMem;               /* Number of entries in aMem */
145   int nOnceFlag;          /* Number of entries in aOnceFlag */
146   int nChildMem;          /* Number of memory cells for child frame */
147   int nChildCsr;          /* Number of cursors for child frame */
148   int nChange;            /* Statement changes (Vdbe.nChanges)     */
149 };
150 
151 #define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
152 
153 /*
154 ** A value for VdbeCursor.cacheValid that means the cache is always invalid.
155 */
156 #define CACHE_STALE 0
157 
158 /*
159 ** Internally, the vdbe manipulates nearly all SQL values as Mem
160 ** structures. Each Mem struct may cache multiple representations (string,
161 ** integer etc.) of the same value.
162 */
163 struct Mem {
164   sqlite3 *db;        /* The associated database connection */
165   char *z;            /* String or BLOB value */
166   double r;           /* Real value */
167   union {
168     i64 i;              /* Integer value used when MEM_Int is set in flags */
169     int nZero;          /* Used when bit MEM_Zero is set in flags */
170     FuncDef *pDef;      /* Used only when flags==MEM_Agg */
171     RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
172     VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
173   } u;
174   int n;              /* Number of characters in string value, excluding '\0' */
175   u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
176   u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
177 #ifdef SQLITE_DEBUG
178   Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
179   void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
180 #endif
181   void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
182   char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
183 };
184 
185 /* One or more of the following flags are set to indicate the validOK
186 ** representations of the value stored in the Mem struct.
187 **
188 ** If the MEM_Null flag is set, then the value is an SQL NULL value.
189 ** No other flags may be set in this case.
190 **
191 ** If the MEM_Str flag is set then Mem.z points at a string representation.
192 ** Usually this is encoded in the same unicode encoding as the main
193 ** database (see below for exceptions). If the MEM_Term flag is also
194 ** set, then the string is nul terminated. The MEM_Int and MEM_Real
195 ** flags may coexist with the MEM_Str flag.
196 */
197 #define MEM_Null      0x0001   /* Value is NULL */
198 #define MEM_Str       0x0002   /* Value is a string */
199 #define MEM_Int       0x0004   /* Value is an integer */
200 #define MEM_Real      0x0008   /* Value is a real number */
201 #define MEM_Blob      0x0010   /* Value is a BLOB */
202 #define MEM_AffMask   0x001f   /* Mask of affinity bits */
203 #define MEM_RowSet    0x0020   /* Value is a RowSet object */
204 #define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
205 #define MEM_Undefined 0x0080   /* Value is undefined */
206 #define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
207 #define MEM_TypeMask  0x01ff   /* Mask of type bits */
208 
209 
210 /* Whenever Mem contains a valid string or blob representation, one of
211 ** the following flags must be set to determine the memory management
212 ** policy for Mem.z.  The MEM_Term flag tells us whether or not the
213 ** string is \000 or \u0000 terminated
214 */
215 #define MEM_Term      0x0200   /* String rep is nul terminated */
216 #define MEM_Dyn       0x0400   /* Need to call Mem.xDel() on Mem.z */
217 #define MEM_Static    0x0800   /* Mem.z points to a static string */
218 #define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
219 #define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
220 #define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
221 #ifdef SQLITE_OMIT_INCRBLOB
222   #undef MEM_Zero
223   #define MEM_Zero 0x0000
224 #endif
225 
226 /*
227 ** Clear any existing type flags from a Mem and replace them with f
228 */
229 #define MemSetTypeFlag(p, f) \
230    ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
231 
232 /*
233 ** Return true if a memory cell is not marked as invalid.  This macro
234 ** is for use inside assert() statements only.
235 */
236 #ifdef SQLITE_DEBUG
237 #define memIsValid(M)  ((M)->flags & MEM_Undefined)==0
238 #endif
239 
240 /*
241 ** Each auxilliary data pointer stored by a user defined function
242 ** implementation calling sqlite3_set_auxdata() is stored in an instance
243 ** of this structure. All such structures associated with a single VM
244 ** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed
245 ** when the VM is halted (if not before).
246 */
247 struct AuxData {
248   int iOp;                        /* Instruction number of OP_Function opcode */
249   int iArg;                       /* Index of function argument. */
250   void *pAux;                     /* Aux data pointer */
251   void (*xDelete)(void *);        /* Destructor for the aux data */
252   AuxData *pNext;                 /* Next element in list */
253 };
254 
255 /*
256 ** The "context" argument for a installable function.  A pointer to an
257 ** instance of this structure is the first argument to the routines used
258 ** implement the SQL functions.
259 **
260 ** There is a typedef for this structure in sqlite.h.  So all routines,
261 ** even the public interface to SQLite, can use a pointer to this structure.
262 ** But this file is the only place where the internal details of this
263 ** structure are known.
264 **
265 ** This structure is defined inside of vdbeInt.h because it uses substructures
266 ** (Mem) which are only defined there.
267 */
268 struct sqlite3_context {
269   FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
270   Mem s;                /* The return value is stored here */
271   Mem *pMem;            /* Memory cell used to store aggregate context */
272   CollSeq *pColl;       /* Collating sequence */
273   Vdbe *pVdbe;          /* The VM that owns this context */
274   int iOp;              /* Instruction number of OP_Function */
275   int isError;          /* Error code returned by the function. */
276   u8 skipFlag;          /* Skip skip accumulator loading if true */
277   u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
278 };
279 
280 /*
281 ** An Explain object accumulates indented output which is helpful
282 ** in describing recursive data structures.
283 */
284 struct Explain {
285   Vdbe *pVdbe;       /* Attach the explanation to this Vdbe */
286   StrAccum str;      /* The string being accumulated */
287   int nIndent;       /* Number of elements in aIndent */
288   u16 aIndent[100];  /* Levels of indentation */
289   char zBase[100];   /* Initial space */
290 };
291 
292 /* A bitfield type for use inside of structures.  Always follow with :N where
293 ** N is the number of bits.
294 */
295 typedef unsigned bft;  /* Bit Field Type */
296 
297 /*
298 ** An instance of the virtual machine.  This structure contains the complete
299 ** state of the virtual machine.
300 **
301 ** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
302 ** is really a pointer to an instance of this structure.
303 **
304 ** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
305 ** any virtual table method invocations made by the vdbe program. It is
306 ** set to 2 for xDestroy method calls and 1 for all other methods. This
307 ** variable is used for two purposes: to allow xDestroy methods to execute
308 ** "DROP TABLE" statements and to prevent some nasty side effects of
309 ** malloc failure when SQLite is invoked recursively by a virtual table
310 ** method function.
311 */
312 struct Vdbe {
313   sqlite3 *db;            /* The database connection that owns this statement */
314   Op *aOp;                /* Space to hold the virtual machine's program */
315   Mem *aMem;              /* The memory locations */
316   Mem **apArg;            /* Arguments to currently executing user function */
317   Mem *aColName;          /* Column names to return */
318   Mem *pResultSet;        /* Pointer to an array of results */
319   Parse *pParse;          /* Parsing context used to create this Vdbe */
320   int nMem;               /* Number of memory locations currently allocated */
321   int nOp;                /* Number of instructions in the program */
322   int nCursor;            /* Number of slots in apCsr[] */
323   u32 magic;              /* Magic number for sanity checking */
324   char *zErrMsg;          /* Error message written here */
325   Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
326   VdbeCursor **apCsr;     /* One element of this array for each open cursor */
327   Mem *aVar;              /* Values for the OP_Variable opcode. */
328   char **azVar;           /* Name of variables */
329   ynVar nVar;             /* Number of entries in aVar[] */
330   ynVar nzVar;            /* Number of entries in azVar[] */
331   u32 cacheCtr;           /* VdbeCursor row cache generation counter */
332   int pc;                 /* The program counter */
333   int rc;                 /* Value to return */
334   u16 nResColumn;         /* Number of columns in one row of the result set */
335   u8 errorAction;         /* Recovery action to do in case of an error */
336   u8 minWriteFileFormat;  /* Minimum file format for writable database files */
337   bft explain:2;          /* True if EXPLAIN present on SQL command */
338   bft inVtabMethod:2;     /* See comments above */
339   bft changeCntOn:1;      /* True to update the change-counter */
340   bft expired:1;          /* True if the VM needs to be recompiled */
341   bft runOnlyOnce:1;      /* Automatically expire on reset */
342   bft usesStmtJournal:1;  /* True if uses a statement journal */
343   bft readOnly:1;         /* True for statements that do not write */
344   bft bIsReader:1;        /* True for statements that read */
345   bft isPrepareV2:1;      /* True if prepared with prepare_v2() */
346   bft doingRerun:1;       /* True if rerunning after an auto-reprepare */
347   int nChange;            /* Number of db changes made since last reset */
348   yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
349   yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
350   int iStatement;         /* Statement number (or 0 if has not opened stmt) */
351   u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
352 #ifndef SQLITE_OMIT_TRACE
353   i64 startTime;          /* Time when query started - used for profiling */
354 #endif
355   i64 iCurrentTime;       /* Value of julianday('now') for this statement */
356   i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
357   i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
358   i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
359   char *zSql;             /* Text of the SQL statement that generated this */
360   void *pFree;            /* Free this when deleting the vdbe */
361 #ifdef SQLITE_ENABLE_TREE_EXPLAIN
362   Explain *pExplain;      /* The explainer */
363   char *zExplain;         /* Explanation of data structures */
364 #endif
365   VdbeFrame *pFrame;      /* Parent frame */
366   VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
367   int nFrame;             /* Number of frames in pFrame list */
368   u32 expmask;            /* Binding to these vars invalidates VM */
369   SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
370   int nOnceFlag;          /* Size of array aOnceFlag[] */
371   u8 *aOnceFlag;          /* Flags for OP_Once */
372   AuxData *pAuxData;      /* Linked list of auxdata allocations */
373 };
374 
375 /*
376 ** The following are allowed values for Vdbe.magic
377 */
378 #define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
379 #define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
380 #define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
381 #define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
382 
383 /*
384 ** Function prototypes
385 */
386 void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
387 void sqliteVdbePopStack(Vdbe*,int);
388 int sqlite3VdbeCursorMoveto(VdbeCursor*);
389 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
390 void sqlite3VdbePrintOp(FILE*, int, Op*);
391 #endif
392 u32 sqlite3VdbeSerialTypeLen(u32);
393 u32 sqlite3VdbeSerialType(Mem*, int);
394 u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
395 u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
396 void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);
397 
398 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
399 int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
400 int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
401 int sqlite3VdbeExec(Vdbe*);
402 int sqlite3VdbeList(Vdbe*);
403 int sqlite3VdbeHalt(Vdbe*);
404 int sqlite3VdbeChangeEncoding(Mem *, int);
405 int sqlite3VdbeMemTooBig(Mem*);
406 int sqlite3VdbeMemCopy(Mem*, const Mem*);
407 void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
408 void sqlite3VdbeMemMove(Mem*, Mem*);
409 int sqlite3VdbeMemNulTerminate(Mem*);
410 int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
411 void sqlite3VdbeMemSetInt64(Mem*, i64);
412 #ifdef SQLITE_OMIT_FLOATING_POINT
413 # define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
414 #else
415   void sqlite3VdbeMemSetDouble(Mem*, double);
416 #endif
417 void sqlite3VdbeMemSetNull(Mem*);
418 void sqlite3VdbeMemSetZeroBlob(Mem*,int);
419 void sqlite3VdbeMemSetRowSet(Mem*);
420 int sqlite3VdbeMemMakeWriteable(Mem*);
421 int sqlite3VdbeMemStringify(Mem*, int);
422 i64 sqlite3VdbeIntValue(Mem*);
423 int sqlite3VdbeMemIntegerify(Mem*);
424 double sqlite3VdbeRealValue(Mem*);
425 void sqlite3VdbeIntegerAffinity(Mem*);
426 int sqlite3VdbeMemRealify(Mem*);
427 int sqlite3VdbeMemNumerify(Mem*);
428 int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
429 void sqlite3VdbeMemRelease(Mem *p);
430 void sqlite3VdbeMemReleaseExternal(Mem *p);
431 #define VdbeMemDynamic(X)  \
432   (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
433 #define VdbeMemRelease(X)  \
434   if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
435 int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
436 const char *sqlite3OpcodeName(int);
437 int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
438 int sqlite3VdbeCloseStatement(Vdbe *, int);
439 void sqlite3VdbeFrameDelete(VdbeFrame*);
440 int sqlite3VdbeFrameRestore(VdbeFrame *);
441 int sqlite3VdbeTransferError(Vdbe *p);
442 
443 int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
444 void sqlite3VdbeSorterReset(sqlite3 *, VdbeSorter *);
445 void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
446 int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
447 int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
448 int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
449 int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
450 int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);
451 
452 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
453   void sqlite3VdbeEnter(Vdbe*);
454   void sqlite3VdbeLeave(Vdbe*);
455 #else
456 # define sqlite3VdbeEnter(X)
457 # define sqlite3VdbeLeave(X)
458 #endif
459 
460 #ifdef SQLITE_DEBUG
461 void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
462 int sqlite3VdbeCheckMemInvariants(Mem*);
463 #endif
464 
465 #ifndef SQLITE_OMIT_FOREIGN_KEY
466 int sqlite3VdbeCheckFk(Vdbe *, int);
467 #else
468 # define sqlite3VdbeCheckFk(p,i) 0
469 #endif
470 
471 int sqlite3VdbeMemTranslate(Mem*, u8);
472 #ifdef SQLITE_DEBUG
473   void sqlite3VdbePrintSql(Vdbe*);
474   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
475 #endif
476 int sqlite3VdbeMemHandleBom(Mem *pMem);
477 
478 #ifndef SQLITE_OMIT_INCRBLOB
479   int sqlite3VdbeMemExpandBlob(Mem *);
480   #define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
481 #else
482   #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
483   #define ExpandBlob(P) SQLITE_OK
484 #endif
485 
486 #endif /* !defined(_VDBEINT_H_) */
487