xref: /sqlite-3.40.0/src/vdbeInt.h (revision 962f9669)
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   i8 iDb;               /* Index of cursor database in db->aDb[] (or -1) */
72   u8 nullRow;           /* True if pointing to a row with no data */
73   u8 rowidIsValid;      /* True if lastRowid is valid */
74   u8 deferredMoveto;    /* A call to sqlite3BtreeMoveto() is needed */
75   Bool useRandomRowid:1;/* Generate new record numbers semi-randomly */
76   Bool isTable:1;       /* True if a table requiring integer keys */
77   Bool isOrdered:1;     /* True if the underlying table is BTREE_UNORDERED */
78   sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
79   i64 seqCount;         /* Sequence counter */
80   i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
81   i64 lastRowid;        /* Rowid being deleted by OP_Delete */
82   VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */
83 
84   /* Cached information about the header for the data record that the
85   ** cursor is currently pointing to.  Only valid if cacheStatus matches
86   ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
87   ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
88   ** the cache is out of date.
89   **
90   ** aRow might point to (ephemeral) data for the current row, or it might
91   ** be NULL.
92   */
93   u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
94   u32 payloadSize;      /* Total number of bytes in the record */
95   u32 szRow;            /* Byte available in aRow */
96   u32 iHdrOffset;       /* Offset to next unparsed byte of the header */
97   const u8 *aRow;       /* Data for the current row, if all on one page */
98   u32 aType[1];         /* Type values for all entries in the record */
99   /* 2*nField extra array elements allocated for aType[], beyond the one
100   ** static element declared in the structure.  nField total array slots for
101   ** aType[] and nField+1 array slots for aOffset[] */
102 };
103 typedef struct VdbeCursor VdbeCursor;
104 
105 /*
106 ** When a sub-program is executed (OP_Program), a structure of this type
107 ** is allocated to store the current value of the program counter, as
108 ** well as the current memory cell array and various other frame specific
109 ** values stored in the Vdbe struct. When the sub-program is finished,
110 ** these values are copied back to the Vdbe from the VdbeFrame structure,
111 ** restoring the state of the VM to as it was before the sub-program
112 ** began executing.
113 **
114 ** The memory for a VdbeFrame object is allocated and managed by a memory
115 ** cell in the parent (calling) frame. When the memory cell is deleted or
116 ** overwritten, the VdbeFrame object is not freed immediately. Instead, it
117 ** is linked into the Vdbe.pDelFrame list. The contents of the Vdbe.pDelFrame
118 ** list is deleted when the VM is reset in VdbeHalt(). The reason for doing
119 ** this instead of deleting the VdbeFrame immediately is to avoid recursive
120 ** calls to sqlite3VdbeMemRelease() when the memory cells belonging to the
121 ** child frame are released.
122 **
123 ** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
124 ** set to NULL if the currently executing frame is the main program.
125 */
126 typedef struct VdbeFrame VdbeFrame;
127 struct VdbeFrame {
128   Vdbe *v;                /* VM this frame belongs to */
129   VdbeFrame *pParent;     /* Parent of this frame, or NULL if parent is main */
130   Op *aOp;                /* Program instructions for parent frame */
131   Mem *aMem;              /* Array of memory cells for parent frame */
132   u8 *aOnceFlag;          /* Array of OP_Once flags for parent frame */
133   VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
134   void *token;            /* Copy of SubProgram.token */
135   i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
136   int nCursor;            /* Number of entries in apCsr */
137   int pc;                 /* Program Counter in parent (calling) frame */
138   int nOp;                /* Size of aOp array */
139   int nMem;               /* Number of entries in aMem */
140   int nOnceFlag;          /* Number of entries in aOnceFlag */
141   int nChildMem;          /* Number of memory cells for child frame */
142   int nChildCsr;          /* Number of cursors for child frame */
143   int nChange;            /* Statement changes (Vdbe.nChanges)     */
144 };
145 
146 #define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
147 
148 /*
149 ** A value for VdbeCursor.cacheValid that means the cache is always invalid.
150 */
151 #define CACHE_STALE 0
152 
153 /*
154 ** Internally, the vdbe manipulates nearly all SQL values as Mem
155 ** structures. Each Mem struct may cache multiple representations (string,
156 ** integer etc.) of the same value.
157 */
158 struct Mem {
159   sqlite3 *db;        /* The associated database connection */
160   char *z;            /* String or BLOB value */
161   double r;           /* Real value */
162   union {
163     i64 i;              /* Integer value used when MEM_Int is set in flags */
164     int nZero;          /* Used when bit MEM_Zero is set in flags */
165     FuncDef *pDef;      /* Used only when flags==MEM_Agg */
166     RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
167     VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
168   } u;
169   int n;              /* Number of characters in string value, excluding '\0' */
170   u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
171   u8  memType;        /* Lower 5 bits of flags */
172   u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
173 #ifdef SQLITE_DEBUG
174   Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
175   void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
176 #endif
177   void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
178   char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
179 };
180 
181 /* One or more of the following flags are set to indicate the validOK
182 ** representations of the value stored in the Mem struct.
183 **
184 ** If the MEM_Null flag is set, then the value is an SQL NULL value.
185 ** No other flags may be set in this case.
186 **
187 ** If the MEM_Str flag is set then Mem.z points at a string representation.
188 ** Usually this is encoded in the same unicode encoding as the main
189 ** database (see below for exceptions). If the MEM_Term flag is also
190 ** set, then the string is nul terminated. The MEM_Int and MEM_Real
191 ** flags may coexist with the MEM_Str flag.
192 */
193 #define MEM_Null      0x0001   /* Value is NULL */
194 #define MEM_Str       0x0002   /* Value is a string */
195 #define MEM_Int       0x0004   /* Value is an integer */
196 #define MEM_Real      0x0008   /* Value is a real number */
197 #define MEM_Blob      0x0010   /* Value is a BLOB */
198 #define MEM_RowSet    0x0020   /* Value is a RowSet object */
199 #define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
200 #define MEM_Undefined 0x0080   /* Value is undefined */
201 #define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
202 #define MEM_TypeMask  0x01ff   /* Mask of type bits */
203 
204 
205 /* Whenever Mem contains a valid string or blob representation, one of
206 ** the following flags must be set to determine the memory management
207 ** policy for Mem.z.  The MEM_Term flag tells us whether or not the
208 ** string is \000 or \u0000 terminated
209 */
210 #define MEM_Term      0x0200   /* String rep is nul terminated */
211 #define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
212 #define MEM_Static    0x0800   /* Mem.z points to a static string */
213 #define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
214 #define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
215 #define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
216 #ifdef SQLITE_OMIT_INCRBLOB
217   #undef MEM_Zero
218   #define MEM_Zero 0x0000
219 #endif
220 
221 /*
222 ** Clear any existing type flags from a Mem and replace them with f
223 */
224 #define MemSetTypeFlag(p, f) \
225    ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
226 
227 /*
228 ** Return true if a memory cell is not marked as invalid.  This macro
229 ** is for use inside assert() statements only.
230 */
231 #ifdef SQLITE_DEBUG
232 #define memIsValid(M)  ((M)->flags & MEM_Undefined)==0
233 #endif
234 
235 /*
236 ** Each auxilliary data pointer stored by a user defined function
237 ** implementation calling sqlite3_set_auxdata() is stored in an instance
238 ** of this structure. All such structures associated with a single VM
239 ** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed
240 ** when the VM is halted (if not before).
241 */
242 struct AuxData {
243   int iOp;                        /* Instruction number of OP_Function opcode */
244   int iArg;                       /* Index of function argument. */
245   void *pAux;                     /* Aux data pointer */
246   void (*xDelete)(void *);        /* Destructor for the aux data */
247   AuxData *pNext;                 /* Next element in list */
248 };
249 
250 /*
251 ** The "context" argument for a installable function.  A pointer to an
252 ** instance of this structure is the first argument to the routines used
253 ** implement the SQL functions.
254 **
255 ** There is a typedef for this structure in sqlite.h.  So all routines,
256 ** even the public interface to SQLite, can use a pointer to this structure.
257 ** But this file is the only place where the internal details of this
258 ** structure are known.
259 **
260 ** This structure is defined inside of vdbeInt.h because it uses substructures
261 ** (Mem) which are only defined there.
262 */
263 struct sqlite3_context {
264   FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
265   Mem s;                /* The return value is stored here */
266   Mem *pMem;            /* Memory cell used to store aggregate context */
267   CollSeq *pColl;       /* Collating sequence */
268   Vdbe *pVdbe;          /* The VM that owns this context */
269   int iOp;              /* Instruction number of OP_Function */
270   int isError;          /* Error code returned by the function. */
271   u8 skipFlag;          /* Skip skip accumulator loading if true */
272   u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
273 };
274 
275 /*
276 ** An Explain object accumulates indented output which is helpful
277 ** in describing recursive data structures.
278 */
279 struct Explain {
280   Vdbe *pVdbe;       /* Attach the explanation to this Vdbe */
281   StrAccum str;      /* The string being accumulated */
282   int nIndent;       /* Number of elements in aIndent */
283   u16 aIndent[100];  /* Levels of indentation */
284   char zBase[100];   /* Initial space */
285 };
286 
287 /* A bitfield type for use inside of structures.  Always follow with :N where
288 ** N is the number of bits.
289 */
290 typedef unsigned bft;  /* Bit Field Type */
291 
292 /*
293 ** An instance of the virtual machine.  This structure contains the complete
294 ** state of the virtual machine.
295 **
296 ** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
297 ** is really a pointer to an instance of this structure.
298 **
299 ** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
300 ** any virtual table method invocations made by the vdbe program. It is
301 ** set to 2 for xDestroy method calls and 1 for all other methods. This
302 ** variable is used for two purposes: to allow xDestroy methods to execute
303 ** "DROP TABLE" statements and to prevent some nasty side effects of
304 ** malloc failure when SQLite is invoked recursively by a virtual table
305 ** method function.
306 */
307 struct Vdbe {
308   sqlite3 *db;            /* The database connection that owns this statement */
309   Op *aOp;                /* Space to hold the virtual machine's program */
310   Mem *aMem;              /* The memory locations */
311   Mem **apArg;            /* Arguments to currently executing user function */
312   Mem *aColName;          /* Column names to return */
313   Mem *pResultSet;        /* Pointer to an array of results */
314   Parse *pParse;          /* Parsing context used to create this Vdbe */
315   int nMem;               /* Number of memory locations currently allocated */
316   int nOp;                /* Number of instructions in the program */
317   int nCursor;            /* Number of slots in apCsr[] */
318   u32 magic;              /* Magic number for sanity checking */
319   char *zErrMsg;          /* Error message written here */
320   Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
321   VdbeCursor **apCsr;     /* One element of this array for each open cursor */
322   Mem *aVar;              /* Values for the OP_Variable opcode. */
323   char **azVar;           /* Name of variables */
324   ynVar nVar;             /* Number of entries in aVar[] */
325   ynVar nzVar;            /* Number of entries in azVar[] */
326   u32 cacheCtr;           /* VdbeCursor row cache generation counter */
327   int pc;                 /* The program counter */
328   int rc;                 /* Value to return */
329   u16 nResColumn;         /* Number of columns in one row of the result set */
330   u8 errorAction;         /* Recovery action to do in case of an error */
331   u8 minWriteFileFormat;  /* Minimum file format for writable database files */
332   bft explain:2;          /* True if EXPLAIN present on SQL command */
333   bft inVtabMethod:2;     /* See comments above */
334   bft changeCntOn:1;      /* True to update the change-counter */
335   bft expired:1;          /* True if the VM needs to be recompiled */
336   bft runOnlyOnce:1;      /* Automatically expire on reset */
337   bft usesStmtJournal:1;  /* True if uses a statement journal */
338   bft readOnly:1;         /* True for statements that do not write */
339   bft bIsReader:1;        /* True for statements that read */
340   bft isPrepareV2:1;      /* True if prepared with prepare_v2() */
341   bft doingRerun:1;       /* True if rerunning after an auto-reprepare */
342   int nChange;            /* Number of db changes made since last reset */
343   yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
344   yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
345   int iStatement;         /* Statement number (or 0 if has not opened stmt) */
346   u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
347 #ifndef SQLITE_OMIT_TRACE
348   i64 startTime;          /* Time when query started - used for profiling */
349 #endif
350   i64 iCurrentTime;       /* Value of julianday('now') for this statement */
351   i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
352   i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
353   i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
354   char *zSql;             /* Text of the SQL statement that generated this */
355   void *pFree;            /* Free this when deleting the vdbe */
356 #ifdef SQLITE_ENABLE_TREE_EXPLAIN
357   Explain *pExplain;      /* The explainer */
358   char *zExplain;         /* Explanation of data structures */
359 #endif
360   VdbeFrame *pFrame;      /* Parent frame */
361   VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
362   int nFrame;             /* Number of frames in pFrame list */
363   u32 expmask;            /* Binding to these vars invalidates VM */
364   SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
365   int nOnceFlag;          /* Size of array aOnceFlag[] */
366   u8 *aOnceFlag;          /* Flags for OP_Once */
367   AuxData *pAuxData;      /* Linked list of auxdata allocations */
368 };
369 
370 /*
371 ** The following are allowed values for Vdbe.magic
372 */
373 #define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
374 #define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
375 #define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
376 #define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
377 
378 /*
379 ** Function prototypes
380 */
381 void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
382 void sqliteVdbePopStack(Vdbe*,int);
383 int sqlite3VdbeCursorMoveto(VdbeCursor*);
384 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
385 void sqlite3VdbePrintOp(FILE*, int, Op*);
386 #endif
387 u32 sqlite3VdbeSerialTypeLen(u32);
388 u32 sqlite3VdbeSerialType(Mem*, int);
389 u32 sqlite3VdbeSerialPut(unsigned char*, Mem*, u32);
390 u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
391 void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);
392 
393 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
394 int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
395 int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
396 int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
397 int sqlite3VdbeExec(Vdbe*);
398 int sqlite3VdbeList(Vdbe*);
399 int sqlite3VdbeHalt(Vdbe*);
400 int sqlite3VdbeChangeEncoding(Mem *, int);
401 int sqlite3VdbeMemTooBig(Mem*);
402 int sqlite3VdbeMemCopy(Mem*, const Mem*);
403 void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
404 void sqlite3VdbeMemMove(Mem*, Mem*);
405 int sqlite3VdbeMemNulTerminate(Mem*);
406 int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
407 void sqlite3VdbeMemSetInt64(Mem*, i64);
408 #ifdef SQLITE_OMIT_FLOATING_POINT
409 # define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
410 #else
411   void sqlite3VdbeMemSetDouble(Mem*, double);
412 #endif
413 void sqlite3VdbeMemSetNull(Mem*);
414 void sqlite3VdbeMemSetZeroBlob(Mem*,int);
415 void sqlite3VdbeMemSetRowSet(Mem*);
416 int sqlite3VdbeMemMakeWriteable(Mem*);
417 int sqlite3VdbeMemStringify(Mem*, int);
418 i64 sqlite3VdbeIntValue(Mem*);
419 int sqlite3VdbeMemIntegerify(Mem*);
420 double sqlite3VdbeRealValue(Mem*);
421 void sqlite3VdbeIntegerAffinity(Mem*);
422 int sqlite3VdbeMemRealify(Mem*);
423 int sqlite3VdbeMemNumerify(Mem*);
424 int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
425 void sqlite3VdbeMemRelease(Mem *p);
426 void sqlite3VdbeMemReleaseExternal(Mem *p);
427 #define VdbeMemDynamic(X)  \
428   (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
429 #define VdbeMemRelease(X)  \
430   if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
431 int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
432 const char *sqlite3OpcodeName(int);
433 int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
434 int sqlite3VdbeCloseStatement(Vdbe *, int);
435 void sqlite3VdbeFrameDelete(VdbeFrame*);
436 int sqlite3VdbeFrameRestore(VdbeFrame *);
437 #define sqlite3VdbeMemStoreType(X)  (X)->memType = (u8)((X)->flags&0x1f)
438 /* void sqlite3VdbeMemStoreType(Mem *pMem); */
439 int sqlite3VdbeTransferError(Vdbe *p);
440 
441 int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
442 void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
443 int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
444 int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
445 int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
446 int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
447 int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int, int *);
448 
449 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
450   void sqlite3VdbeEnter(Vdbe*);
451   void sqlite3VdbeLeave(Vdbe*);
452 #else
453 # define sqlite3VdbeEnter(X)
454 # define sqlite3VdbeLeave(X)
455 #endif
456 
457 #ifdef SQLITE_DEBUG
458 void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
459 #endif
460 
461 #ifndef SQLITE_OMIT_FOREIGN_KEY
462 int sqlite3VdbeCheckFk(Vdbe *, int);
463 #else
464 # define sqlite3VdbeCheckFk(p,i) 0
465 #endif
466 
467 int sqlite3VdbeMemTranslate(Mem*, u8);
468 #ifdef SQLITE_DEBUG
469   void sqlite3VdbePrintSql(Vdbe*);
470   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
471 #endif
472 int sqlite3VdbeMemHandleBom(Mem *pMem);
473 
474 #ifndef SQLITE_OMIT_INCRBLOB
475   int sqlite3VdbeMemExpandBlob(Mem *);
476   #define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
477 #else
478   #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
479   #define ExpandBlob(P) SQLITE_OK
480 #endif
481 
482 #endif /* !defined(_VDBEINT_H_) */
483