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Overview
Comment:Enable the b-tree cursor object's overflow page-number cache, which is normally enabled only for incr-blob cursors, for all cursors.
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SHA1: da59198505990a4fe832be7932117c7e014955b7
User & Date: dan 2014-03-11 20:33:04.219
Original Comment: Enable the b-tree cursor objects overflow page-number cache, which is normally enabled only for incr-blob cursors, for all cursors.
References
2017-01-27
00:31
Simplify the accessPayload() routine so that it always populates the overflow page cache. In the one case where populating the page cache can lead to problems, simply invalidate the cache as soon as accessPayload() returns. This simplification reduces code size and helps accessPayload() to run a little faster. This backs out the eOp==2 mode of accessPayload() added by check-in [da59198505]. (check-in: 68e7a8c676 user: drh tags: trunk)
Context
2014-03-11
23:40
Combine the various boolean fields of the BtCursor object into a single bit-vector. This allows setting or clearing more than one boolean at a time and makes the overflow-pgno-cache branch faster than trunk on speedtest1. (check-in: 968fec44d7 user: drh tags: overflow-pgno-cache)
20:33
Enable the b-tree cursor object's overflow page-number cache, which is normally enabled only for incr-blob cursors, for all cursors. (check-in: da59198505 user: dan tags: overflow-pgno-cache)
15:27
Version 3.8.4.1 (check-in: 018d317b12 user: drh tags: trunk, release, version-3.8.4.1)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
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*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
  return sqlite3_mutex_held(p->pBt->mutex);
}
#endif


#ifndef SQLITE_OMIT_INCRBLOB
/*
** Invalidate the overflow page-list cache for cursor pCur, if any.

*/
static void invalidateOverflowCache(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  sqlite3_free(pCur->aOverflow);
  pCur->aOverflow = 0;
}

/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
static void invalidateAllOverflowCache(BtShared *pBt){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  for(p=pBt->pCursor; p; p=p->pNext){
    invalidateOverflowCache(p);
  }
}


/*
** This function is called before modifying the contents of a table
** to invalidate any incrblob cursors that are open on the
** row or one of the rows being modified.
**
** If argument isClearTable is true, then the entire contents of the
** table is about to be deleted. In this case invalidate all incrblob







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*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
  return sqlite3_mutex_held(p->pBt->mutex);
}
#endif



/*
** Invalidate the overflow cache of the cursor passed as the first argument.
** on the shared btree structure pBt.
*/
#define invalidateOverflowCache(pCur) (pCur->bOvflValid = 0)





/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
static void invalidateAllOverflowCache(BtShared *pBt){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  for(p=pBt->pCursor; p; p=p->pNext){
    invalidateOverflowCache(p);
  }
}

#ifndef SQLITE_OMIT_INCRBLOB
/*
** This function is called before modifying the contents of a table
** to invalidate any incrblob cursors that are open on the
** row or one of the rows being modified.
**
** If argument isClearTable is true, then the entire contents of the
** table is about to be deleted. In this case invalidate all incrblob
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    if( p->isIncrblobHandle && (isClearTable || p->info.nKey==iRow) ){
      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  /* Stub functions when INCRBLOB is omitted */
  #define invalidateOverflowCache(x)
  #define invalidateAllOverflowCache(x)
  #define invalidateIncrblobCursors(x,y,z)
#endif /* SQLITE_OMIT_INCRBLOB */

/*
** Set bit pgno of the BtShared.pHasContent bitvec. This is called 
** when a page that previously contained data becomes a free-list leaf 
** page.







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    if( p->isIncrblobHandle && (isClearTable || p->info.nKey==iRow) ){
      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  /* Stub function when INCRBLOB is omitted */


  #define invalidateIncrblobCursors(x,y,z)
#endif /* SQLITE_OMIT_INCRBLOB */

/*
** Set bit pgno of the BtShared.pHasContent bitvec. This is called 
** when a page that previously contained data becomes a free-list leaf 
** page.
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    if( pCur->pNext ){
      pCur->pNext->pPrev = pCur->pPrev;
    }
    for(i=0; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);
    }
    unlockBtreeIfUnused(pBt);
    invalidateOverflowCache(pCur);
    /* sqlite3_free(pCur); */
    sqlite3BtreeLeave(pBtree);
  }
  return SQLITE_OK;
}

/*







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    if( pCur->pNext ){
      pCur->pNext->pPrev = pCur->pPrev;
    }
    for(i=0; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);
    }
    unlockBtreeIfUnused(pBt);
    sqlite3DbFree(pBtree->db, pCur->aOverflow);
    /* sqlite3_free(pCur); */
    sqlite3BtreeLeave(pBtree);
  }
  return SQLITE_OK;
}

/*
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    memcpy(pBuf, pPayload, nByte);
  }
  return SQLITE_OK;
}

/*
** This function is used to read or overwrite payload information
** for the entry that the pCur cursor is pointing to. If the eOp
** parameter is 0, this is a read operation (data copied into
** buffer pBuf). If it is non-zero, a write (data copied from
** buffer pBuf).



**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
**
** The content being read or written might appear on the main page
** or be scattered out on multiple overflow pages.
**
** If the BtCursor.isIncrblobHandle flag is set, and the current
** cursor entry uses one or more overflow pages, this function

** allocates space for and lazily popluates the overflow page-list 
** cache array (BtCursor.aOverflow). Subsequent calls use this
** cache to make seeking to the supplied offset more efficient.
**
** Once an overflow page-list cache has been allocated, it may be
** invalidated if some other cursor writes to the same table, or if
** the cursor is moved to a different row. Additionally, in auto-vacuum
** mode, the following events may invalidate an overflow page-list cache.
**
**   * An incremental vacuum,







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    memcpy(pBuf, pPayload, nByte);
  }
  return SQLITE_OK;
}

/*
** This function is used to read or overwrite payload information
** for the entry that the pCur cursor is pointing to. The eOp

** argument is interpreted as follows:
**
**   0: The operation is a read. Populate the overflow cache.
**   1: The operation is a write. Populate the overflow cache.
**   2: The operation is a read. Do not populate the overflow cache.
**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
**
** The content being read or written might appear on the main page
** or be scattered out on multiple overflow pages.
**

** If the current cursor entry uses one or more overflow pages and the
** eOp argument is not 2, this function may allocate space for and lazily 
** popluates the overflow page-list cache array (BtCursor.aOverflow). 
** Subsequent calls use this cache to make seeking to the supplied offset 
** more efficient.
**
** Once an overflow page-list cache has been allocated, it may be
** invalidated if some other cursor writes to the same table, or if
** the cursor is moved to a different row. Additionally, in auto-vacuum
** mode, the following events may invalidate an overflow page-list cache.
**
**   * An incremental vacuum,
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  /* Check if data must be read/written to/from the btree page itself. */
  if( offset<pCur->info.nLocal ){
    int a = amt;
    if( a+offset>pCur->info.nLocal ){
      a = pCur->info.nLocal - offset;
    }
    rc = copyPayload(&aPayload[offset], pBuf, a, eOp, pPage->pDbPage);
    offset = 0;
    pBuf += a;
    amt -= a;
  }else{
    offset -= pCur->info.nLocal;
  }

  if( rc==SQLITE_OK && amt>0 ){
    const u32 ovflSize = pBt->usableSize - 4;  /* Bytes content per ovfl page */
    Pgno nextPage;

    nextPage = get4byte(&aPayload[pCur->info.nLocal]);

#ifndef SQLITE_OMIT_INCRBLOB
    /* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
    ** has not been allocated, allocate it now. The array is sized at
    ** one entry for each overflow page in the overflow chain. The
    ** page number of the first overflow page is stored in aOverflow[0],
    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
    ** (the cache is lazily populated).
    */
    if( pCur->isIncrblobHandle && !pCur->aOverflow ){
      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;

      pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
      /* nOvfl is always positive.  If it were zero, fetchPayload would have
      ** been used instead of this routine. */

      if( ALWAYS(nOvfl) && !pCur->aOverflow ){
        rc = SQLITE_NOMEM;








      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
    ** directly to it.
    */
    if( pCur->aOverflow && pCur->aOverflow[offset/ovflSize] ){
      iIdx = (offset/ovflSize);
      nextPage = pCur->aOverflow[iIdx];
      offset = (offset%ovflSize);
    }
#endif

    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){

#ifndef SQLITE_OMIT_INCRBLOB
      /* If required, populate the overflow page-list cache. */
      if( pCur->aOverflow ){
        assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
        pCur->aOverflow[iIdx] = nextPage;
      }
#endif

      if( offset>=ovflSize ){
        /* The only reason to read this page is to obtain the page
        ** number for the next page in the overflow chain. The page
        ** data is not required. So first try to lookup the overflow
        ** page-list cache, if any, then fall back to the getOverflowPage()
        ** function.
        */
#ifndef SQLITE_OMIT_INCRBLOB
        if( pCur->aOverflow && pCur->aOverflow[iIdx+1] ){
          nextPage = pCur->aOverflow[iIdx+1];
        } else 
#endif
          rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
        offset -= ovflSize;
      }else{
        /* Need to read this page properly. It contains some of the
        ** range of data that is being read (eOp==0) or written (eOp!=0).
        */
#ifdef SQLITE_DIRECT_OVERFLOW_READ







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  /* Check if data must be read/written to/from the btree page itself. */
  if( offset<pCur->info.nLocal ){
    int a = amt;
    if( a+offset>pCur->info.nLocal ){
      a = pCur->info.nLocal - offset;
    }
    rc = copyPayload(&aPayload[offset], pBuf, a, (eOp & 0x01), pPage->pDbPage);
    offset = 0;
    pBuf += a;
    amt -= a;
  }else{
    offset -= pCur->info.nLocal;
  }

  if( rc==SQLITE_OK && amt>0 ){
    const u32 ovflSize = pBt->usableSize - 4;  /* Bytes content per ovfl page */
    Pgno nextPage;

    nextPage = get4byte(&aPayload[pCur->info.nLocal]);


    /* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
    ** has not been allocated, allocate it now. The array is sized at
    ** one entry for each overflow page in the overflow chain. The
    ** page number of the first overflow page is stored in aOverflow[0],
    ** etc. A value of 0 in the aOverflow[] array means "not yet known"
    ** (the cache is lazily populated).
    */
    if( eOp!=2 && !pCur->bOvflValid ){
      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
      if( nOvfl>pCur->nOvflAlloc ){
        Pgno *aNew = (Pgno*)sqlite3DbRealloc(
            pCur->pBtree->db, pCur->aOverflow, nOvfl*2*sizeof(Pgno)

        );
        if( aNew==0 ){
          rc = SQLITE_NOMEM;
        }else{
          pCur->nOvflAlloc = nOvfl*2;
          pCur->aOverflow = aNew;
        }
      }
      if( rc==SQLITE_OK ){
        memset(pCur->aOverflow, 0, nOvfl*sizeof(Pgno));
        pCur->bOvflValid = 1;
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
    ** directly to it.
    */
    if( pCur->bOvflValid && pCur->aOverflow[offset/ovflSize] ){
      iIdx = (offset/ovflSize);
      nextPage = pCur->aOverflow[iIdx];
      offset = (offset%ovflSize);
    }


    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){


      /* If required, populate the overflow page-list cache. */
      if( pCur->bOvflValid ){
        assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
        pCur->aOverflow[iIdx] = nextPage;
      }


      if( offset>=ovflSize ){
        /* The only reason to read this page is to obtain the page
        ** number for the next page in the overflow chain. The page
        ** data is not required. So first try to lookup the overflow
        ** page-list cache, if any, then fall back to the getOverflowPage()
        ** function.
        */

        if( pCur->bOvflValid && pCur->aOverflow[iIdx+1] ){
          nextPage = pCur->aOverflow[iIdx+1];
        } else 

          rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
        offset -= ovflSize;
      }else{
        /* Need to read this page properly. It contains some of the
        ** range of data that is being read (eOp==0) or written (eOp!=0).
        */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
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        **   4) there is no open write-transaction, and
        **   5) the database is not a WAL database,
        **
        ** then data can be read directly from the database file into the
        ** output buffer, bypassing the page-cache altogether. This speeds
        ** up loading large records that span many overflow pages.
        */
        if( eOp==0                                             /* (1) */
         && offset==0                                          /* (2) */
         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;
          rc = sqlite3PagerAcquire(pBt->pPager, nextPage, &pDbPage,
              (eOp==0 ? PAGER_GET_READONLY : 0)
          );
          if( rc==SQLITE_OK ){
            aPayload = sqlite3PagerGetData(pDbPage);
            nextPage = get4byte(aPayload);
            rc = copyPayload(&aPayload[offset+4], pBuf, a, eOp, pDbPage);
            sqlite3PagerUnref(pDbPage);
            offset = 0;
          }
        }
        amt -= a;
        pBuf += a;
      }







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        **   4) there is no open write-transaction, and
        **   5) the database is not a WAL database,
        **
        ** then data can be read directly from the database file into the
        ** output buffer, bypassing the page-cache altogether. This speeds
        ** up loading large records that span many overflow pages.
        */
        if( (eOp&0x01)==0                                      /* (1) */
         && offset==0                                          /* (2) */
         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;
          rc = sqlite3PagerAcquire(pBt->pPager, nextPage, &pDbPage,
              ((eOp&0x01)==0 ? PAGER_GET_READONLY : 0)
          );
          if( rc==SQLITE_OK ){
            aPayload = sqlite3PagerGetData(pDbPage);
            nextPage = get4byte(aPayload);
            rc = copyPayload(&aPayload[offset+4], pBuf, a, (eOp&0x01), pDbPage);
            sqlite3PagerUnref(pDbPage);
            offset = 0;
          }
        }
        amt -= a;
        pBuf += a;
      }
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  MemPage *pRoot;
  int rc = SQLITE_OK;

  assert( cursorHoldsMutex(pCur) );
  assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
  assert( CURSOR_VALID   < CURSOR_REQUIRESEEK );
  assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );

  if( pCur->eState>=CURSOR_REQUIRESEEK ){
    if( pCur->eState==CURSOR_FAULT ){
      assert( pCur->skipNext!=SQLITE_OK );
      return pCur->skipNext;
    }
    sqlite3BtreeClearCursor(pCur);
  }







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  MemPage *pRoot;
  int rc = SQLITE_OK;

  assert( cursorHoldsMutex(pCur) );
  assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
  assert( CURSOR_VALID   < CURSOR_REQUIRESEEK );
  assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );
  invalidateOverflowCache(pCur);
  if( pCur->eState>=CURSOR_REQUIRESEEK ){
    if( pCur->eState==CURSOR_FAULT ){
      assert( pCur->skipNext!=SQLITE_OK );
      return pCur->skipNext;
    }
    sqlite3BtreeClearCursor(pCur);
  }
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          nCell = (int)pCur->info.nKey;
          pCellKey = sqlite3Malloc( nCell );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM;
            goto moveto_finish;
          }
          pCur->aiIdx[pCur->iPage] = (u16)idx;
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 0);
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
          sqlite3_free(pCellKey);
        }







|







4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
          nCell = (int)pCur->info.nKey;
          pCellKey = sqlite3Malloc( nCell );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM;
            goto moveto_finish;
          }
          pCur->aiIdx[pCur->iPage] = (u16)idx;
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 2);
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
          sqlite3_free(pCellKey);
        }
4771
4772
4773
4774
4775
4776
4777

4778
4779
4780
4781
4782
4783
4784
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );

  if( pCur->eState!=CURSOR_VALID ){
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      *pRes = 0;
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){







>







4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  invalidateOverflowCache(pCur);
  if( pCur->eState!=CURSOR_VALID ){
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      *pRes = 0;
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
4866
4867
4868
4869
4870
4871
4872

4873
4874
4875
4876
4877
4878
4879
  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );

  pCur->atLast = 0;
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ){
        *pRes = 0;
        return rc;







>







4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  invalidateOverflowCache(pCur);
  pCur->atLast = 0;
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ){
        *pRes = 0;
        return rc;
8420
8421
8422
8423
8424
8425
8426
8427
8428
8429
8430
8431
8432
8433
8434
8435
8436
8437
8438
8439
8440
8441
8442
8443
8444
8445
8446
  assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
  assert( pCsr->apPage[pCsr->iPage]->intKey );

  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
}

/* 
** Set a flag on this cursor to cache the locations of pages from the 
** overflow list for the current row. This is used by cursors opened
** for incremental blob IO only.
**
** This function sets a flag only. The actual page location cache
** (stored in BtCursor.aOverflow[]) is allocated and used by function
** accessPayload() (the worker function for sqlite3BtreeData() and
** sqlite3BtreePutData()).
*/
void sqlite3BtreeCacheOverflow(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  invalidateOverflowCache(pCur);
  pCur->isIncrblobHandle = 1;
}
#endif

/*
** Set both the "read version" (single byte at byte offset 18) and 
** "write version" (single byte at byte offset 19) fields in the database







<
<
|
<
<
<
<
<

|
<
<
<







8422
8423
8424
8425
8426
8427
8428


8429





8430
8431



8432
8433
8434
8435
8436
8437
8438
  assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
  assert( pCsr->apPage[pCsr->iPage]->intKey );

  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
}

/* 


** Mark this cursor as an incremental blob cursor.





*/
void sqlite3BtreeIncrblobCursor(BtCursor *pCur){



  pCur->isIncrblobHandle = 1;
}
#endif

/*
** Set both the "read version" (single byte at byte offset 18) and 
** "write version" (single byte at byte offset 19) fields in the database
Changes to src/btree.h.
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
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 sqlite3BtreeCacheOverflow(BtCursor *);
void sqlite3BtreeClearCursor(BtCursor *);
int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);

#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif







|







183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
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 *);
void sqlite3BtreeClearCursor(BtCursor *);
int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);

#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif
Changes to src/btreeInt.h.
493
494
495
496
497
498
499


500
501
502
503
504
505
506
*/
struct BtCursor {
  Btree *pBtree;            /* The Btree to which this cursor belongs */
  BtShared *pBt;            /* The BtShared this cursor points to */
  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
#ifndef SQLITE_OMIT_INCRBLOB


  Pgno *aOverflow;          /* Cache of overflow page locations */
#endif
  Pgno pgnoRoot;            /* The root page of this tree */
  CellInfo info;            /* A parse of the cell we are pointing at */
  i64 nKey;        /* Size of pKey, or last integer key */
  void *pKey;      /* Saved key that was cursor's last known position */
  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */







>
>







493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
*/
struct BtCursor {
  Btree *pBtree;            /* The Btree to which this cursor belongs */
  BtShared *pBt;            /* The BtShared this cursor points to */
  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
#ifndef SQLITE_OMIT_INCRBLOB
  int nOvflAlloc;           /* Allocated size of aOverflow[] array */
  u8 bOvflValid;            /* True if size and contents of aOverflow[] valid */
  Pgno *aOverflow;          /* Cache of overflow page locations */
#endif
  Pgno pgnoRoot;            /* The root page of this tree */
  CellInfo info;            /* A parse of the cell we are pointing at */
  i64 nKey;        /* Size of pKey, or last integer key */
  void *pKey;      /* Saved key that was cursor's last known position */
  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */
Changes to src/vdbeblob.c.
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
      rc = SQLITE_ERROR;
      sqlite3_finalize(p->pStmt);
      p->pStmt = 0;
    }else{
      p->iOffset = pC->aType[p->iCol + pC->nField];
      p->nByte = sqlite3VdbeSerialTypeLen(type);
      p->pCsr =  pC->pCursor;
      sqlite3BtreeEnterCursor(p->pCsr);
      sqlite3BtreeCacheOverflow(p->pCsr);
      sqlite3BtreeLeaveCursor(p->pCsr);
    }
  }

  if( rc==SQLITE_ROW ){
    rc = SQLITE_OK;
  }else if( p->pStmt ){
    rc = sqlite3_finalize(p->pStmt);







|
<
<







73
74
75
76
77
78
79
80


81
82
83
84
85
86
87
      rc = SQLITE_ERROR;
      sqlite3_finalize(p->pStmt);
      p->pStmt = 0;
    }else{
      p->iOffset = pC->aType[p->iCol + pC->nField];
      p->nByte = sqlite3VdbeSerialTypeLen(type);
      p->pCsr =  pC->pCursor;
      sqlite3BtreeIncrblobCursor(p->pCsr);


    }
  }

  if( rc==SQLITE_ROW ){
    rc = SQLITE_OK;
  }else if( p->pStmt ){
    rc = sqlite3_finalize(p->pStmt);