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Overview
Comment:Btree interface refactoring: (1) The sqlite3BtreeKeySize() interface is renamed to sqlite3BtreeIntegerKey() and modified to work only for table btrees with a rowid. (2) The sqlite3BtreeDataSize() interface is renamed to sqlite3BtreePayloadSize() and modified to work with any btree. (3) The sqlite3BtreeDataFetch() and sqlite3BtreeKeyFetch() routines are combined into a single sqlite3BtreePayloadFetch() routine. The result of these changes is a smaller binary and fewer CPU cycles needed to run queries.
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SHA1: 2d831074cf730dce47de5880d7b4570d04d15fee
User & Date: drh 2016-06-06 01:14:08
References
2016-11-25
19:18
Refactor the sqlite3BtreeKey() and sqlite3BtreeData() internal interfaces into sqlite3BtreePayload() and sqlite3BtreePayloadChecked(), respectively. This is a continuation of the optimization started by check-in [2d831074cf]. The result is a slightly smaller and faster binary. check-in: 49ebc219 user: drh tags: trunk
Context
2016-06-06
01:48
Small performance improvement in the LIKE function. check-in: 5fb0c354 user: drh tags: trunk
01:14
Btree interface refactoring: (1) The sqlite3BtreeKeySize() interface is renamed to sqlite3BtreeIntegerKey() and modified to work only for table btrees with a rowid. (2) The sqlite3BtreeDataSize() interface is renamed to sqlite3BtreePayloadSize() and modified to work with any btree. (3) The sqlite3BtreeDataFetch() and sqlite3BtreeKeyFetch() routines are combined into a single sqlite3BtreePayloadFetch() routine. The result of these changes is a smaller binary and fewer CPU cycles needed to run queries. check-in: 2d831074 user: drh tags: trunk
2016-06-04
21:05
Improved comment on cursorOwnsBtShared(). No changes to code. Closed-Leaf check-in: 5e269c2d user: drh tags: btree-refactor
17:12
Allocate KeyInfo objects from lookaside if possible. check-in: b411107a user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/btree.c.

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**
** Verify that the cursor holds the mutex on its BtShared
*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
  return sqlite3_mutex_held(p->pBt->mutex);
}









static int cursorOwnsBtShared(BtCursor *p){
  assert( cursorHoldsMutex(p) );
  return (p->pBtree->db==p->pBt->db);
}
#endif

/*
................................................................................
** If the cursor is open on an intkey table, then the integer key
** (the rowid) is stored in pCur->nKey and pCur->pKey is left set to
** NULL. If the cursor is open on a non-intkey table, then pCur->pKey is 
** set to point to a malloced buffer pCur->nKey bytes in size containing 
** the key.
*/
static int saveCursorKey(BtCursor *pCur){
  int rc;
  assert( CURSOR_VALID==pCur->eState );
  assert( 0==pCur->pKey );
  assert( cursorHoldsMutex(pCur) );

  rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
  assert( rc==SQLITE_OK );  /* KeySize() cannot fail */

  /* If this is an intKey table, then the above call to BtreeKeySize()
  ** stores the integer key in pCur->nKey. In this case this value is
  ** all that is required. Otherwise, if pCur is not open on an intKey
  ** table, then malloc space for and store the pCur->nKey bytes of key 
  ** data.  */
  if( 0==pCur->curIntKey ){






    void *pKey = sqlite3Malloc( pCur->nKey );
    if( pKey ){
      rc = sqlite3BtreeKey(pCur, 0, (int)pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqlite3_free(pKey);
      }
................................................................................
*/
int sqlite3BtreeCursorIsValid(BtCursor *pCur){
  return pCur && pCur->eState==CURSOR_VALID;
}
#endif /* NDEBUG */

/*
** Set *pSize to the size of the buffer needed to hold the value of
** the key for the current entry.  If the cursor is not pointing
** to a valid entry, *pSize is set to 0. 
**
** For a table with the INTKEY flag set, this routine returns the key
** itself, not the number of bytes in the key.
**
** The caller must position the cursor prior to invoking this routine.
** 
** This routine cannot fail.  It always returns SQLITE_OK.  
*/
int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){

  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );

  getCellInfo(pCur);
  *pSize = pCur->info.nKey;
  return SQLITE_OK;
}

/*
** Set *pSize to the number of bytes of data in the entry the
** cursor currently points to.

**
** The caller must guarantee that the cursor is pointing to a non-NULL
** valid entry.  In other words, the calling procedure must guarantee
** that the cursor has Cursor.eState==CURSOR_VALID.
**
** Failure is not possible.  This function always returns SQLITE_OK.
** It might just as well be a procedure (returning void) but we continue
** to return an integer result code for historical reasons.
*/
int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
  assert( cursorOwnsBtShared(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage>=0 );
  assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
  assert( pCur->apPage[pCur->iPage]->intKeyLeaf==1 );
  getCellInfo(pCur);
  *pSize = pCur->info.nPayload;
  return SQLITE_OK;
}

/*
** Given the page number of an overflow page in the database (parameter
** ovfl), this function finds the page number of the next page in the 
** linked list of overflow pages. If possible, it uses the auto-vacuum
** pointer-map data instead of reading the content of page ovfl to do so. 
................................................................................
** including calls from other threads against the same cache.
** Hence, a mutex on the BtShared should be held prior to calling
** this routine.
**
** These routines is used to get quick access to key and data
** in the common case where no overflow pages are used.
*/
const void *sqlite3BtreeKeyFetch(BtCursor *pCur, u32 *pAmt){
  return fetchPayload(pCur, pAmt);
}
const void *sqlite3BtreeDataFetch(BtCursor *pCur, u32 *pAmt){
  return fetchPayload(pCur, pAmt);
}


/*
** Move the cursor down to a new child page.  The newPgno argument is the
** page number of the child page to move to.







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**
** Verify that the cursor holds the mutex on its BtShared
*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
  return sqlite3_mutex_held(p->pBt->mutex);
}

/* Verify that the cursor and the BtShared agree about what is the current
** database connetion. This is important in shared-cache mode. If the database 
** connection pointers get out-of-sync, it is possible for routines like
** btreeInitPage() to reference an stale connection pointer that references a
** a connection that has already closed.  This routine is used inside assert()
** statements only and for the purpose of double-checking that the btree code
** does keep the database connection pointers up-to-date.
*/
static int cursorOwnsBtShared(BtCursor *p){
  assert( cursorHoldsMutex(p) );
  return (p->pBtree->db==p->pBt->db);
}
#endif

/*
................................................................................
** If the cursor is open on an intkey table, then the integer key
** (the rowid) is stored in pCur->nKey and pCur->pKey is left set to
** NULL. If the cursor is open on a non-intkey table, then pCur->pKey is 
** set to point to a malloced buffer pCur->nKey bytes in size containing 
** the key.
*/
static int saveCursorKey(BtCursor *pCur){
  int rc = SQLITE_OK;
  assert( CURSOR_VALID==pCur->eState );
  assert( 0==pCur->pKey );
  assert( cursorHoldsMutex(pCur) );









  if( pCur->curIntKey ){
    /* Only the rowid is required for a table btree */
    pCur->nKey = sqlite3BtreeIntegerKey(pCur);
  }else{
    /* For an index btree, save the complete key content */
    void *pKey;
    pCur->nKey = sqlite3BtreePayloadSize(pCur);
    pKey = sqlite3Malloc( pCur->nKey );
    if( pKey ){
      rc = sqlite3BtreeKey(pCur, 0, (int)pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqlite3_free(pKey);
      }
................................................................................
*/
int sqlite3BtreeCursorIsValid(BtCursor *pCur){
  return pCur && pCur->eState==CURSOR_VALID;
}
#endif /* NDEBUG */

/*
** Return the value of the integer key or "rowid" for a table btree.
** This routine is only valid for a cursor that is pointing into a
** ordinary table btree.  If the cursor points to an index btree or
** is invalid, the result of this routine is undefined.






*/

i64 sqlite3BtreeIntegerKey(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->curIntKey );
  getCellInfo(pCur);
  return pCur->info.nKey;

}

/*
** Return the number of bytes of payload for the entry that pCur is
** currently pointing to.  For table btrees, this will be the amount
** of data.  For index btrees, this will be the size of the key.
**
** The caller must guarantee that the cursor is pointing to a non-NULL
** valid entry.  In other words, the calling procedure must guarantee
** that the cursor has Cursor.eState==CURSOR_VALID.




*/
u32 sqlite3BtreePayloadSize(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );



  getCellInfo(pCur);
  return pCur->info.nPayload;

}

/*
** Given the page number of an overflow page in the database (parameter
** ovfl), this function finds the page number of the next page in the 
** linked list of overflow pages. If possible, it uses the auto-vacuum
** pointer-map data instead of reading the content of page ovfl to do so. 
................................................................................
** including calls from other threads against the same cache.
** Hence, a mutex on the BtShared should be held prior to calling
** this routine.
**
** These routines is used to get quick access to key and data
** in the common case where no overflow pages are used.
*/
const void *sqlite3BtreePayloadFetch(BtCursor *pCur, u32 *pAmt){



  return fetchPayload(pCur, pAmt);
}


/*
** Move the cursor down to a new child page.  The newPgno argument is the
** page number of the child page to move to.

Changes to src/btree.h.

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int sqlite3BtreeInsert(BtCursor*, const BtreePayload *pPayload,
                       int bias, int seekResult);
int sqlite3BtreeFirst(BtCursor*, int *pRes);
int sqlite3BtreeLast(BtCursor*, int *pRes);
int sqlite3BtreeNext(BtCursor*, int *pRes);
int sqlite3BtreeEof(BtCursor*);
int sqlite3BtreePrevious(BtCursor*, int *pRes);
int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
const void *sqlite3BtreeKeyFetch(BtCursor*, u32 *pAmt);
const void *sqlite3BtreeDataFetch(BtCursor*, u32 *pAmt);
int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeIncrblobCursor(BtCursor *);







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int sqlite3BtreeInsert(BtCursor*, const BtreePayload *pPayload,
                       int bias, int seekResult);
int sqlite3BtreeFirst(BtCursor*, int *pRes);
int sqlite3BtreeLast(BtCursor*, int *pRes);
int sqlite3BtreeNext(BtCursor*, int *pRes);
int sqlite3BtreeEof(BtCursor*);
int sqlite3BtreePrevious(BtCursor*, int *pRes);
i64 sqlite3BtreeIntegerKey(BtCursor*);
int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
const void *sqlite3BtreePayloadFetch(BtCursor*, u32 *pAmt);
u32 sqlite3BtreePayloadSize(BtCursor*);

int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeIncrblobCursor(BtCursor *);

Changes to src/test3.c.

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static int btree_payload_size(
  void *NotUsed,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  const char **argv      /* Text of each argument */
){
  BtCursor *pCur;
  int n2;
  u64 n1;
  char zBuf[50];

  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pCur = sqlite3TestTextToPtr(argv[1]);
  sqlite3BtreeEnter(pCur->pBtree);

  /* The cursor may be in "require-seek" state. If this is the case, the
  ** call to BtreeDataSize() will fix it. */
  sqlite3BtreeDataSize(pCur, (u32*)&n2);
  if( pCur->apPage[pCur->iPage]->intKey ){
    n1 = 0;
  }else{
    sqlite3BtreeKeySize(pCur, (i64*)&n1);
  }

  sqlite3BtreeLeave(pCur->pBtree);
  sqlite3_snprintf(sizeof(zBuf),zBuf, "%d", (int)(n1+n2));
  Tcl_AppendResult(interp, zBuf, 0);
  return SQLITE_OK;
}

/*
** usage:   varint_test  START  MULTIPLIER  COUNT  INCREMENT
**







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static int btree_payload_size(
  void *NotUsed,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  const char **argv      /* Text of each argument */
){
  BtCursor *pCur;
  u32 n;

  char zBuf[50];

  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pCur = sqlite3TestTextToPtr(argv[1]);
  sqlite3BtreeEnter(pCur->pBtree);









  n = sqlite3BtreePayloadSize(pCur);
  sqlite3BtreeLeave(pCur->pBtree);
  sqlite3_snprintf(sizeof(zBuf),zBuf, "%u", n);
  Tcl_AppendResult(interp, zBuf, 0);
  return SQLITE_OK;
}

/*
** usage:   varint_test  START  MULTIPLIER  COUNT  INCREMENT
**

Changes to src/vdbe.c.

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**
** If the OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG bits are set on P5 when
** the result is guaranteed to only be used as the argument of a length()
** or typeof() function, respectively.  The loading of large blobs can be
** skipped for length() and all content loading can be skipped for typeof().
*/
case OP_Column: {
  i64 payloadSize64; /* Number of bytes in the record */
  int p2;            /* column number to retrieve */
  VdbeCursor *pC;    /* The VDBE cursor */
  BtCursor *pCrsr;   /* The BTree cursor */
  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
  int len;           /* The length of the serialized data for the column */
  int i;             /* Loop counter */
  Mem *pDest;        /* Where to write the extracted value */
................................................................................
      }else{
        sqlite3VdbeMemSetNull(pDest);
        goto op_column_out;
      }
    }else{
      assert( pC->eCurType==CURTYPE_BTREE );
      assert( pCrsr );
      if( pC->isTable==0 ){
        assert( sqlite3BtreeCursorIsValid(pCrsr) );
        VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &payloadSize64);
        assert( rc==SQLITE_OK ); /* True because of CursorMoveto() call above */
        /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
        ** payload size, so it is impossible for payloadSize64 to be
        ** larger than 32 bits. */
        assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 );
        pC->aRow = sqlite3BtreeKeyFetch(pCrsr, &avail);
        pC->payloadSize = (u32)payloadSize64;
      }else{
        assert( sqlite3BtreeCursorIsValid(pCrsr) );
        VVA_ONLY(rc =) sqlite3BtreeDataSize(pCrsr, &pC->payloadSize);
        assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
        pC->aRow = sqlite3BtreeDataFetch(pCrsr, &avail);
      }
      assert( avail<=65536 );  /* Maximum page size is 64KiB */
      if( pC->payloadSize <= (u32)avail ){
        pC->szRow = pC->payloadSize;
      }else if( pC->payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
        goto too_big;
      }else{
        pC->szRow = avail;
................................................................................
      if( rc!=SQLITE_OK ){
        goto abort_due_to_error;
      }
      if( res ){
        v = 1;   /* IMP: R-61914-48074 */
      }else{
        assert( sqlite3BtreeCursorIsValid(pC->uc.pCursor) );
        rc = sqlite3BtreeKeySize(pC->uc.pCursor, &v);
        assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
        if( v>=MAX_ROWID ){
          pC->useRandomRowid = 1;
        }else{
          v++;   /* IMP: R-29538-34987 */
        }
      }
    }
................................................................................
  assert( pC->deferredMoveto==0 );

#ifdef SQLITE_DEBUG
  if( pOp->p4type==P4_TABLE && HasRowid(pOp->p4.pTab) && pOp->p5==0 ){
    /* If p5 is zero, the seek operation that positioned the cursor prior to
    ** OP_Delete will have also set the pC->movetoTarget field to the rowid of
    ** the row that is being deleted */
    i64 iKey = 0;
    sqlite3BtreeKeySize(pC->uc.pCursor, &iKey);
    assert( pC->movetoTarget==iKey );
  }
#endif

  /* If the update-hook or pre-update-hook will be invoked, set zDb to
  ** the name of the db to pass as to it. Also set local pTab to a copy
  ** of p4.pTab. Finally, if p5 is true, indicating that this cursor was
................................................................................
  ** VdbeCursor.movetoTarget to the current rowid.  */
  if( pOp->p4type==P4_TABLE && HAS_UPDATE_HOOK(db) ){
    assert( pC->iDb>=0 );
    assert( pOp->p4.pTab!=0 );
    zDb = db->aDb[pC->iDb].zName;
    pTab = pOp->p4.pTab;
    if( (pOp->p5 & OPFLAG_SAVEPOSITION)!=0 && pC->isTable ){
      sqlite3BtreeKeySize(pC->uc.pCursor, &pC->movetoTarget);
    }
  }else{
    zDb = 0;   /* Not needed.  Silence a compiler warning. */
    pTab = 0;  /* Not needed.  Silence a compiler warning. */
  }

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
................................................................................
** of a real table, not a pseudo-table.
*/
case OP_RowKey:
case OP_RowData: {
  VdbeCursor *pC;
  BtCursor *pCrsr;
  u32 n;
  i64 n64;

  pOut = &aMem[pOp->p2];
  memAboutToChange(p, pOut);

  /* Note that RowKey and RowData are really exactly the same instruction */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
................................................................................
  assert( pC->deferredMoveto==0 );
  assert( sqlite3BtreeCursorIsValid(pCrsr) );
#if 0  /* Not required due to the previous to assert() statements */
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc!=SQLITE_OK ) goto abort_due_to_error;
#endif

  if( pC->isTable==0 ){
    assert( !pC->isTable );
    VVA_ONLY(rc =) sqlite3BtreeKeySize(pCrsr, &n64);
    assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
    if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
    }
    n = (u32)n64;
  }else{
    VVA_ONLY(rc =) sqlite3BtreeDataSize(pCrsr, &n);
    assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
    if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
      goto too_big;
    }
  }
  testcase( n==0 );
  if( sqlite3VdbeMemClearAndResize(pOut, MAX(n,32)) ){
    goto no_mem;
  }
  pOut->n = n;
  MemSetTypeFlag(pOut, MEM_Blob);
................................................................................
    assert( pC->uc.pCursor!=0 );
    rc = sqlite3VdbeCursorRestore(pC);
    if( rc ) goto abort_due_to_error;
    if( pC->nullRow ){
      pOut->flags = MEM_Null;
      break;
    }
    rc = sqlite3BtreeKeySize(pC->uc.pCursor, &v);
    assert( rc==SQLITE_OK );  /* Always so because of CursorRestore() above */
  }
  pOut->u.i = v;
  break;
}

/* Opcode: NullRow P1 * * * *
**







<







 







<
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<
<
<
<
<
<
<
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<
<
<
<
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<







 







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<







 







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<







 







|







 







<







 







|
<
<
<
<
<
<
<
<
<
<
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<







 







|
<







2376
2377
2378
2379
2380
2381
2382

2383
2384
2385
2386
2387
2388
2389
....
2428
2429
2430
2431
2432
2433
2434

2435







2436




2437

2438
2439
2440
2441
2442
2443
2444
....
4183
4184
4185
4186
4187
4188
4189
4190

4191
4192
4193
4194
4195
4196
4197
....
4440
4441
4442
4443
4444
4445
4446
4447

4448
4449
4450
4451
4452
4453
4454
....
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
....
4610
4611
4612
4613
4614
4615
4616

4617
4618
4619
4620
4621
4622
4623
....
4641
4642
4643
4644
4645
4646
4647
4648










4649
4650

4651
4652
4653
4654
4655
4656
4657
....
4708
4709
4710
4711
4712
4713
4714
4715

4716
4717
4718
4719
4720
4721
4722
**
** If the OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG bits are set on P5 when
** the result is guaranteed to only be used as the argument of a length()
** or typeof() function, respectively.  The loading of large blobs can be
** skipped for length() and all content loading can be skipped for typeof().
*/
case OP_Column: {

  int p2;            /* column number to retrieve */
  VdbeCursor *pC;    /* The VDBE cursor */
  BtCursor *pCrsr;   /* The BTree cursor */
  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
  int len;           /* The length of the serialized data for the column */
  int i;             /* Loop counter */
  Mem *pDest;        /* Where to write the extracted value */
................................................................................
      }else{
        sqlite3VdbeMemSetNull(pDest);
        goto op_column_out;
      }
    }else{
      assert( pC->eCurType==CURTYPE_BTREE );
      assert( pCrsr );

      assert( sqlite3BtreeCursorIsValid(pCrsr) );







      pC->payloadSize = sqlite3BtreePayloadSize(pCrsr);




      pC->aRow = sqlite3BtreePayloadFetch(pCrsr, &avail);

      assert( avail<=65536 );  /* Maximum page size is 64KiB */
      if( pC->payloadSize <= (u32)avail ){
        pC->szRow = pC->payloadSize;
      }else if( pC->payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
        goto too_big;
      }else{
        pC->szRow = avail;
................................................................................
      if( rc!=SQLITE_OK ){
        goto abort_due_to_error;
      }
      if( res ){
        v = 1;   /* IMP: R-61914-48074 */
      }else{
        assert( sqlite3BtreeCursorIsValid(pC->uc.pCursor) );
        v = sqlite3BtreeIntegerKey(pC->uc.pCursor);

        if( v>=MAX_ROWID ){
          pC->useRandomRowid = 1;
        }else{
          v++;   /* IMP: R-29538-34987 */
        }
      }
    }
................................................................................
  assert( pC->deferredMoveto==0 );

#ifdef SQLITE_DEBUG
  if( pOp->p4type==P4_TABLE && HasRowid(pOp->p4.pTab) && pOp->p5==0 ){
    /* If p5 is zero, the seek operation that positioned the cursor prior to
    ** OP_Delete will have also set the pC->movetoTarget field to the rowid of
    ** the row that is being deleted */
    i64 iKey = sqlite3BtreeIntegerKey(pC->uc.pCursor);

    assert( pC->movetoTarget==iKey );
  }
#endif

  /* If the update-hook or pre-update-hook will be invoked, set zDb to
  ** the name of the db to pass as to it. Also set local pTab to a copy
  ** of p4.pTab. Finally, if p5 is true, indicating that this cursor was
................................................................................
  ** VdbeCursor.movetoTarget to the current rowid.  */
  if( pOp->p4type==P4_TABLE && HAS_UPDATE_HOOK(db) ){
    assert( pC->iDb>=0 );
    assert( pOp->p4.pTab!=0 );
    zDb = db->aDb[pC->iDb].zName;
    pTab = pOp->p4.pTab;
    if( (pOp->p5 & OPFLAG_SAVEPOSITION)!=0 && pC->isTable ){
      pC->movetoTarget = sqlite3BtreeIntegerKey(pC->uc.pCursor);
    }
  }else{
    zDb = 0;   /* Not needed.  Silence a compiler warning. */
    pTab = 0;  /* Not needed.  Silence a compiler warning. */
  }

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
................................................................................
** of a real table, not a pseudo-table.
*/
case OP_RowKey:
case OP_RowData: {
  VdbeCursor *pC;
  BtCursor *pCrsr;
  u32 n;


  pOut = &aMem[pOp->p2];
  memAboutToChange(p, pOut);

  /* Note that RowKey and RowData are really exactly the same instruction */
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  pC = p->apCsr[pOp->p1];
................................................................................
  assert( pC->deferredMoveto==0 );
  assert( sqlite3BtreeCursorIsValid(pCrsr) );
#if 0  /* Not required due to the previous to assert() statements */
  rc = sqlite3VdbeCursorMoveto(pC);
  if( rc!=SQLITE_OK ) goto abort_due_to_error;
#endif

  n = sqlite3BtreePayloadSize(pCrsr);










  if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;

  }
  testcase( n==0 );
  if( sqlite3VdbeMemClearAndResize(pOut, MAX(n,32)) ){
    goto no_mem;
  }
  pOut->n = n;
  MemSetTypeFlag(pOut, MEM_Blob);
................................................................................
    assert( pC->uc.pCursor!=0 );
    rc = sqlite3VdbeCursorRestore(pC);
    if( rc ) goto abort_due_to_error;
    if( pC->nullRow ){
      pOut->flags = MEM_Null;
      break;
    }
    v = sqlite3BtreeIntegerKey(pC->uc.pCursor);

  }
  pOut->u.i = v;
  break;
}

/* Opcode: NullRow P1 * * * *
**

Changes to src/vdbeapi.c.

1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
  }

  /* If the old.* record has not yet been loaded into memory, do so now. */
  if( p->pUnpacked==0 ){
    u32 nRec;
    u8 *aRec;

    rc = sqlite3BtreeDataSize(p->pCsr->uc.pCursor, &nRec);
    if( rc!=SQLITE_OK ) goto preupdate_old_out;
    aRec = sqlite3DbMallocRaw(db, nRec);
    if( !aRec ) goto preupdate_old_out;
    rc = sqlite3BtreeData(p->pCsr->uc.pCursor, 0, nRec, aRec);
    if( rc==SQLITE_OK ){
      p->pUnpacked = vdbeUnpackRecord(&p->keyinfo, nRec, aRec);
      if( !p->pUnpacked ) rc = SQLITE_NOMEM;
    }







|
<







1646
1647
1648
1649
1650
1651
1652
1653

1654
1655
1656
1657
1658
1659
1660
  }

  /* If the old.* record has not yet been loaded into memory, do so now. */
  if( p->pUnpacked==0 ){
    u32 nRec;
    u8 *aRec;

    nRec = sqlite3BtreePayloadSize(p->pCsr->uc.pCursor);

    aRec = sqlite3DbMallocRaw(db, nRec);
    if( !aRec ) goto preupdate_old_out;
    rc = sqlite3BtreeData(p->pCsr->uc.pCursor, 0, nRec, aRec);
    if( rc==SQLITE_OK ){
      p->pUnpacked = vdbeUnpackRecord(&p->keyinfo, nRec, aRec);
      if( !p->pUnpacked ) rc = SQLITE_NOMEM;
    }

Changes to src/vdbeaux.c.

4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
....
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404

  /* Get the size of the index entry.  Only indices entries of less
  ** than 2GiB are support - anything large must be database corruption.
  ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
  ** this code can safely assume that nCellKey is 32-bits  
  */
  assert( sqlite3BtreeCursorIsValid(pCur) );
  VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
  assert( rc==SQLITE_OK );     /* pCur is always valid so KeySize cannot fail */
  assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );

  /* Read in the complete content of the index entry */
  sqlite3VdbeMemInit(&m, db, 0);
  rc = sqlite3VdbeMemFromBtree(pCur, 0, (u32)nCellKey, 1, &m);
  if( rc ){
    return rc;
................................................................................
  int rc;
  BtCursor *pCur;
  Mem m;

  assert( pC->eCurType==CURTYPE_BTREE );
  pCur = pC->uc.pCursor;
  assert( sqlite3BtreeCursorIsValid(pCur) );
  VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
  assert( rc==SQLITE_OK );    /* pCur is always valid so KeySize cannot fail */
  /* nCellKey will always be between 0 and 0xffffffff because of the way
  ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
  if( nCellKey<=0 || nCellKey>0x7fffffff ){
    *res = 0;
    return SQLITE_CORRUPT_BKPT;
  }
  sqlite3VdbeMemInit(&m, db, 0);







|
<







 







|
<







4311
4312
4313
4314
4315
4316
4317
4318

4319
4320
4321
4322
4323
4324
4325
....
4388
4389
4390
4391
4392
4393
4394
4395

4396
4397
4398
4399
4400
4401
4402

  /* Get the size of the index entry.  Only indices entries of less
  ** than 2GiB are support - anything large must be database corruption.
  ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
  ** this code can safely assume that nCellKey is 32-bits  
  */
  assert( sqlite3BtreeCursorIsValid(pCur) );
  nCellKey = sqlite3BtreePayloadSize(pCur);

  assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );

  /* Read in the complete content of the index entry */
  sqlite3VdbeMemInit(&m, db, 0);
  rc = sqlite3VdbeMemFromBtree(pCur, 0, (u32)nCellKey, 1, &m);
  if( rc ){
    return rc;
................................................................................
  int rc;
  BtCursor *pCur;
  Mem m;

  assert( pC->eCurType==CURTYPE_BTREE );
  pCur = pC->uc.pCursor;
  assert( sqlite3BtreeCursorIsValid(pCur) );
  nCellKey = sqlite3BtreePayloadSize(pCur);

  /* nCellKey will always be between 0 and 0xffffffff because of the way
  ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
  if( nCellKey<=0 || nCellKey>0x7fffffff ){
    *res = 0;
    return SQLITE_CORRUPT_BKPT;
  }
  sqlite3VdbeMemInit(&m, db, 0);

Changes to src/vdbeblob.c.

411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
      ** SQLITE_UPDATE where the PK columns do not change is handled in the 
      ** same way as an SQLITE_DELETE (the SQLITE_DELETE code is actually
      ** slightly more efficient). Since you cannot write to a PK column
      ** using the incremental-blob API, this works. For the sessions module
      ** anyhow.
      */
      sqlite3_int64 iKey;
      sqlite3BtreeKeySize(p->pCsr, &iKey);
      sqlite3VdbePreUpdateHook(
          v, v->apCsr[0], SQLITE_DELETE, p->zDb, p->pTab, iKey, -1
      );
    }
#endif

    rc = xCall(p->pCsr, iOffset+p->iOffset, n, z);







|







411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
      ** SQLITE_UPDATE where the PK columns do not change is handled in the 
      ** same way as an SQLITE_DELETE (the SQLITE_DELETE code is actually
      ** slightly more efficient). Since you cannot write to a PK column
      ** using the incremental-blob API, this works. For the sessions module
      ** anyhow.
      */
      sqlite3_int64 iKey;
      iKey = sqlite3BtreeIntegerKey(p->pCsr);
      sqlite3VdbePreUpdateHook(
          v, v->apCsr[0], SQLITE_DELETE, p->zDb, p->pTab, iKey, -1
      );
    }
#endif

    rc = xCall(p->pCsr, iOffset+p->iOffset, n, z);

Changes to src/vdbemem.c.

987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005

  assert( sqlite3BtreeCursorIsValid(pCur) );
  assert( !VdbeMemDynamic(pMem) );

  /* Note: the calls to BtreeKeyFetch() and DataFetch() below assert() 
  ** that both the BtShared and database handle mutexes are held. */
  assert( (pMem->flags & MEM_RowSet)==0 );
  if( key ){
    zData = (char *)sqlite3BtreeKeyFetch(pCur, &available);
  }else{
    zData = (char *)sqlite3BtreeDataFetch(pCur, &available);
  }
  assert( zData!=0 );

  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else{







<
|
<
<
<







987
988
989
990
991
992
993

994



995
996
997
998
999
1000
1001

  assert( sqlite3BtreeCursorIsValid(pCur) );
  assert( !VdbeMemDynamic(pMem) );

  /* Note: the calls to BtreeKeyFetch() and DataFetch() below assert() 
  ** that both the BtShared and database handle mutexes are held. */
  assert( (pMem->flags & MEM_RowSet)==0 );

  zData = (char *)sqlite3BtreePayloadFetch(pCur, &available);



  assert( zData!=0 );

  if( offset+amt<=available ){
    pMem->z = &zData[offset];
    pMem->flags = MEM_Blob|MEM_Ephem;
    pMem->n = (int)amt;
  }else{