System.Data.SQLite

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.8.2"
#define SQLITE_VERSION_NUMBER 3008002
#define SQLITE_SOURCE_ID      "2013-11-11 19:56:35 f58d57017199421167dae8ebc67db2f19be45082"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

** ^[sqlite3_free()] is used to free idxPtr if and only if
** needToFreeIdxPtr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of a particular
** strategy. A cost of N indicates that the cost of the strategy is similar
** to a linear scan of an SQLite table with N rows. A cost of log(N) 
** indicates that the expense of the operation is similar to that of a
** binary search on a unique indexed field of an SQLite table with N rows.
**
** ^The estimatedRows value is an estimate of the number of rows that
** will be returned by the strategy.
**
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
** structure for SQLite version 3.8.2. If a virtual table extension is
** used with an SQLite version earlier than 3.8.2, the results of attempting 
** to read or write the estimatedRows field are undefined (but are likely 
** to included crashing the application). The estimatedRows field should
** therefore only be used if [sqlite3_libversion_number()] returns a
** value greater than or equal to 3008002.
*/
struct sqlite3_index_info {
  /* Inputs */
  int nConstraint;           /* Number of entries in aConstraint */
  struct sqlite3_index_constraint {
     int iColumn;              /* Column on left-hand side of constraint */
     unsigned char op;         /* Constraint operator */

    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
    unsigned char omit;      /* Do not code a test for this constraint */
  } *aConstraintUsage;
  int idxNum;                /* Number used to identify the index */
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;           /* Estimated cost of using this index */
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
};

/*
** CAPI3REF: Virtual Table Constraint Operator Codes
**
** These macros defined the allowed values for the
** [sqlite3_index_info].aConstraint[].op field.  Each value represents

  sqlite3_vfs *pVfs,        /* Used to get maximum path name length */
  const char *zName,        /* Name of the file (UTF-8) */
  sqlite3_file *id,         /* Write the SQLite file handle here */
  int flags,                /* Open mode flags */
  int *pOutFlags            /* Status return flags */
){
  HANDLE h;
  DWORD lastErrno = 0;
  DWORD dwDesiredAccess;
  DWORD dwShareMode;
  DWORD dwCreationDisposition;
  DWORD dwFlagsAndAttributes = 0;
#if SQLITE_OS_WINCE
  int isTemp = 0;
#endif

  sqlite3_vfs *pVfs,          /* Not used on win32 */
  const char *zFilename,      /* Name of file to delete */
  int syncDir                 /* Not used on win32 */
){
  int cnt = 0;
  int rc;
  DWORD attr;
  DWORD lastErrno = 0;
  void *zConverted;
  UNUSED_PARAMETER(pVfs);
  UNUSED_PARAMETER(syncDir);

  SimulateIOError(return SQLITE_IOERR_DELETE);
  OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));

  sqlite3_vfs *pVfs,         /* Not used on win32 */
  const char *zFilename,     /* Name of file to check */
  int flags,                 /* Type of test to make on this file */
  int *pResOut               /* OUT: Result */
){
  DWORD attr;
  int rc = 0;
  DWORD lastErrno = 0;
  void *zConverted;
  UNUSED_PARAMETER(pVfs);

  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
           zFilename, flags, pResOut));

    int i;
    VdbeOpList const *pIn = aOp;
    for(i=0; i<nOp; i++, pIn++){
      int p2 = pIn->p2;
      VdbeOp *pOut = &p->aOp[i+addr];
      pOut->opcode = pIn->opcode;
      pOut->p1 = pIn->p1;
      if( p2<0 ){
        assert( sqlite3OpcodeProperty[pOut->opcode] & OPFLG_JUMP );
        pOut->p2 = addr + ADDR(p2);
      }else{
        pOut->p2 = p2;
      }
      pOut->p3 = pIn->p3;
      pOut->p4type = P4_NOTUSED;
      pOut->p4.p = 0;

      testcase( pOp->p5==2 );
      testcase( pOp->p5==3 );
      testcase( pOp->p5==4 );
      u.ab.zType = azType[pOp->p5-1];
    }else{
      u.ab.zType = 0;
    }
    assert( u.ab.zType!=0 || pOp->p4.z!=0 );
    u.ab.zLogFmt = "abort at %d in [%s]: %s";
    if( u.ab.zType && pOp->p4.z ){
      sqlite3SetString(&p->zErrMsg, db, "%s constraint failed: %s",
                       u.ab.zType, pOp->p4.z);
    }else if( pOp->p4.z ){
      sqlite3SetString(&p->zErrMsg, db, "%s", pOp->p4.z);
    }else{
      sqlite3SetString(&p->zErrMsg, db, "%s constraint failed", u.ab.zType);


    }
    sqlite3_log(pOp->p1, u.ab.zLogFmt, pc, p->zSql, p->zErrMsg);
  }
  rc = sqlite3VdbeHalt(p);
  assert( rc==SQLITE_BUSY || rc==SQLITE_OK || rc==SQLITE_ERROR );
  if( rc==SQLITE_BUSY ){
    p->rc = rc = SQLITE_BUSY;

      assert( (u.ap.payloadSize64 & SQLITE_MAX_U32)==(u64)u.ap.payloadSize64 );
      u.ap.payloadSize = (u32)u.ap.payloadSize64;
    }else{
      assert( sqlite3BtreeCursorIsValid(u.ap.pCrsr) );
      VVA_ONLY(rc =) sqlite3BtreeDataSize(u.ap.pCrsr, &u.ap.payloadSize);
      assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
    }
  }else{
    assert( u.ap.pC->pseudoTableReg>0 );
    u.ap.pReg = &aMem[u.ap.pC->pseudoTableReg];
    if( u.ap.pC->multiPseudo ){
      sqlite3VdbeMemShallowCopy(u.ap.pDest, u.ap.pReg+u.ap.p2, MEM_Ephem);
      Deephemeralize(u.ap.pDest);
      goto op_column_out;
    }
    assert( u.ap.pReg->flags & MEM_Blob );
    assert( memIsValid(u.ap.pReg) );
    u.ap.payloadSize = u.ap.pReg->n;
    u.ap.zRec = u.ap.pReg->z;
    u.ap.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
    assert( u.ap.payloadSize==0 || u.ap.zRec!=0 );



  }

  /* If u.ap.payloadSize is 0, then just store a NULL.  This can happen because of
  ** nullRow or because of a corrupt database. */
  if( u.ap.payloadSize==0 ){
    MemSetTypeFlag(u.ap.pDest, MEM_Null);
    goto op_column_out;

case OP_Count: {         /* out2-prerelease */
#if 0  /* local variables moved into u.as */
  i64 nEntry;
  BtCursor *pCrsr;
#endif /* local variables moved into u.as */

  u.as.pCrsr = p->apCsr[pOp->p1]->pCursor;
  assert( u.as.pCrsr );
  rc = sqlite3BtreeCount(u.as.pCrsr, &u.as.nEntry);



  pOut->u.i = u.as.nEntry;
  break;
}
#endif

/* Opcode: Savepoint P1 * * P4 *
**

  u.bd.pC = p->apCsr[pOp->p1];
  assert( u.bd.pC!=0 );
  assert( u.bd.pC->pseudoTableReg==0 );
  assert( OP_SeekLe == OP_SeekLt+1 );
  assert( OP_SeekGe == OP_SeekLt+2 );
  assert( OP_SeekGt == OP_SeekLt+3 );
  assert( u.bd.pC->isOrdered );
  assert( u.bd.pC->pCursor!=0 );
  u.bd.oc = pOp->opcode;
  u.bd.pC->nullRow = 0;
  if( u.bd.pC->isTable ){
    /* The input value in P3 might be of any type: integer, real, string,
    ** blob, or NULL.  But it needs to be an integer before we can do
    ** the seek, so covert it. */
    pIn3 = &aMem[pOp->p3];
    applyNumericAffinity(pIn3);
    u.bd.iKey = sqlite3VdbeIntValue(pIn3);
    u.bd.pC->rowidIsValid = 0;

    /* If the P3 value could not be converted into an integer without
    ** loss of information, then special processing is required... */
    if( (pIn3->flags & MEM_Int)==0 ){
      if( (pIn3->flags & MEM_Real)==0 ){
        /* If the P3 value cannot be converted into any kind of a number,
        ** then the seek is not possible, so jump to P2 */
        pc = pOp->p2 - 1;
        break;
      }
      /* If we reach this point, then the P3 value must be a floating
      ** point number. */
      assert( (pIn3->flags & MEM_Real)!=0 );

      if( u.bd.iKey==SMALLEST_INT64 && (pIn3->r<(double)u.bd.iKey || pIn3->r>0) ){
        /* The P3 value is too large in magnitude to be expressed as an
        ** integer. */
        u.bd.res = 1;
        if( pIn3->r<0 ){
          if( u.bd.oc>=OP_SeekGe ){  assert( u.bd.oc==OP_SeekGe || u.bd.oc==OP_SeekGt );
            rc = sqlite3BtreeFirst(u.bd.pC->pCursor, &u.bd.res);
            if( rc!=SQLITE_OK ) goto abort_due_to_error;
          }
        }else{
          if( u.bd.oc<=OP_SeekLe ){  assert( u.bd.oc==OP_SeekLt || u.bd.oc==OP_SeekLe );
            rc = sqlite3BtreeLast(u.bd.pC->pCursor, &u.bd.res);
            if( rc!=SQLITE_OK ) goto abort_due_to_error;
          }
        }
        if( u.bd.res ){
          pc = pOp->p2 - 1;
        }
        break;
      }else if( u.bd.oc==OP_SeekLt || u.bd.oc==OP_SeekGe ){
        /* Use the ceiling() function to convert real->int */
        if( pIn3->r > (double)u.bd.iKey ) u.bd.iKey++;
      }else{
        /* Use the floor() function to convert real->int */
        assert( u.bd.oc==OP_SeekLe || u.bd.oc==OP_SeekGt );
        if( pIn3->r < (double)u.bd.iKey ) u.bd.iKey--;
      }
    }
    rc = sqlite3BtreeMovetoUnpacked(u.bd.pC->pCursor, 0, (u64)u.bd.iKey, 0, &u.bd.res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    if( u.bd.res==0 ){
      u.bd.pC->rowidIsValid = 1;
      u.bd.pC->lastRowid = u.bd.iKey;
    }
  }else{
    u.bd.nField = pOp->p4.i;
    assert( pOp->p4type==P4_INT32 );
    assert( u.bd.nField>0 );
    u.bd.r.pKeyInfo = u.bd.pC->pKeyInfo;
    u.bd.r.nField = (u16)u.bd.nField;

    /* The next line of code computes as follows, only faster:
    **   if( u.bd.oc==OP_SeekGt || u.bd.oc==OP_SeekLe ){
    **     u.bd.r.flags = UNPACKED_INCRKEY;
    **   }else{
    **     u.bd.r.flags = 0;
    **   }
    */
    u.bd.r.flags = (u8)(UNPACKED_INCRKEY * (1 & (u.bd.oc - OP_SeekLt)));
    assert( u.bd.oc!=OP_SeekGt || u.bd.r.flags==UNPACKED_INCRKEY );
    assert( u.bd.oc!=OP_SeekLe || u.bd.r.flags==UNPACKED_INCRKEY );
    assert( u.bd.oc!=OP_SeekGe || u.bd.r.flags==0 );
    assert( u.bd.oc!=OP_SeekLt || u.bd.r.flags==0 );

    u.bd.r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
    { int i; for(i=0; i<u.bd.r.nField; i++) assert( memIsValid(&u.bd.r.aMem[i]) ); }
#endif
    ExpandBlob(u.bd.r.aMem);
    rc = sqlite3BtreeMovetoUnpacked(u.bd.pC->pCursor, &u.bd.r, 0, 0, &u.bd.res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    u.bd.pC->rowidIsValid = 0;
  }
  u.bd.pC->deferredMoveto = 0;
  u.bd.pC->cacheStatus = CACHE_STALE;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  if( u.bd.oc>=OP_SeekGe ){  assert( u.bd.oc==OP_SeekGe || u.bd.oc==OP_SeekGt );
    if( u.bd.res<0 || (u.bd.res==0 && u.bd.oc==OP_SeekGt) ){
      rc = sqlite3BtreeNext(u.bd.pC->pCursor, &u.bd.res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
      u.bd.pC->rowidIsValid = 0;
    }else{
      u.bd.res = 0;
    }
  }else{
    assert( u.bd.oc==OP_SeekLt || u.bd.oc==OP_SeekLe );
    if( u.bd.res>0 || (u.bd.res==0 && u.bd.oc==OP_SeekLt) ){
      rc = sqlite3BtreePrevious(u.bd.pC->pCursor, &u.bd.res);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
      u.bd.pC->rowidIsValid = 0;
    }else{
      /* u.bd.res might be negative because the table is empty.  Check to
      ** see if this is the case.
      */
      u.bd.res = sqlite3BtreeEof(u.bd.pC->pCursor);
    }
  }
  assert( pOp->p2>0 );
  if( u.bd.res ){







    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: Seek P1 P2 * * *
** Synopsis:  intkey=r[P2]

#if 0  /* local variables moved into u.be */
  VdbeCursor *pC;
#endif /* local variables moved into u.be */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.be.pC = p->apCsr[pOp->p1];
  assert( u.be.pC!=0 );
  assert( u.be.pC->pCursor!=0 );
  assert( u.be.pC->isTable );
  u.be.pC->nullRow = 0;
  pIn2 = &aMem[pOp->p2];
  u.be.pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
  u.be.pC->rowidIsValid = 0;
  u.be.pC->deferredMoveto = 1;

  break;
}
  

/* Opcode: Found P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**

  u.bf.alreadyExists = 0;
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  assert( pOp->p4type==P4_INT32 );
  u.bf.pC = p->apCsr[pOp->p1];
  assert( u.bf.pC!=0 );
  pIn3 = &aMem[pOp->p3];
  assert( u.bf.pC->pCursor!=0 );

  assert( u.bf.pC->isTable==0 );
  if( pOp->p4.i>0 ){
    u.bf.r.pKeyInfo = u.bf.pC->pKeyInfo;
    u.bf.r.nField = (u16)pOp->p4.i;
    u.bf.r.aMem = pIn3;
#ifdef SQLITE_DEBUG
    {
      int i;
      for(i=0; i<u.bf.r.nField; i++){
        assert( memIsValid(&u.bf.r.aMem[i]) );
        if( i ) REGISTER_TRACE(pOp->p3+i, &u.bf.r.aMem[i]);
      }
    }
#endif
    u.bf.r.flags = UNPACKED_PREFIX_MATCH;
    u.bf.pIdxKey = &u.bf.r;
  }else{
    u.bf.pIdxKey = sqlite3VdbeAllocUnpackedRecord(
        u.bf.pC->pKeyInfo, u.bf.aTempRec, sizeof(u.bf.aTempRec), &u.bf.pFree
    );
    if( u.bf.pIdxKey==0 ) goto no_mem;
    assert( pIn3->flags & MEM_Blob );
    assert( (pIn3->flags & MEM_Zero)==0 );  /* zeroblobs already expanded */
    sqlite3VdbeRecordUnpack(u.bf.pC->pKeyInfo, pIn3->n, pIn3->z, u.bf.pIdxKey);
    u.bf.pIdxKey->flags |= UNPACKED_PREFIX_MATCH;
  }
  if( pOp->opcode==OP_NoConflict ){
    /* For the OP_NoConflict opcode, take the jump if any of the
    ** input fields are NULL, since any key with a NULL will not
    ** conflict */
    for(u.bf.ii=0; u.bf.ii<u.bf.r.nField; u.bf.ii++){
      if( u.bf.r.aMem[u.bf.ii].flags & MEM_Null ){
        pc = pOp->p2 - 1;
        break;
      }
    }
  }
  rc = sqlite3BtreeMovetoUnpacked(u.bf.pC->pCursor, u.bf.pIdxKey, 0, 0, &u.bf.res);
  if( pOp->p4.i==0 ){
    sqlite3DbFree(db, u.bf.pFree);
  }
  if( rc!=SQLITE_OK ){
    break;
  }
  u.bf.pC->seekResult = u.bf.res;
  u.bf.alreadyExists = (u.bf.res==0);
  u.bf.pC->nullRow = 1-u.bf.alreadyExists;
  u.bf.pC->deferredMoveto = 0;
  u.bf.pC->cacheStatus = CACHE_STALE;

  if( pOp->opcode==OP_Found ){
    if( u.bf.alreadyExists ) pc = pOp->p2 - 1;
  }else{
    if( !u.bf.alreadyExists ) pc = pOp->p2 - 1;
  }
  break;
}

  assert( pIn3->flags & MEM_Int );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bg.pC = p->apCsr[pOp->p1];
  assert( u.bg.pC!=0 );
  assert( u.bg.pC->isTable );
  assert( u.bg.pC->pseudoTableReg==0 );
  u.bg.pCrsr = u.bg.pC->pCursor;
  assert( u.bg.pCrsr!=0 );
  u.bg.res = 0;
  u.bg.iKey = pIn3->u.i;
  rc = sqlite3BtreeMovetoUnpacked(u.bg.pCrsr, 0, u.bg.iKey, 0, &u.bg.res);
  u.bg.pC->lastRowid = pIn3->u.i;
  u.bg.pC->rowidIsValid = u.bg.res==0 ?1:0;
  u.bg.pC->nullRow = 0;
  u.bg.pC->cacheStatus = CACHE_STALE;
  u.bg.pC->deferredMoveto = 0;
  if( u.bg.res!=0 ){
    pc = pOp->p2 - 1;
    assert( u.bg.pC->rowidIsValid==0 );
  }
  u.bg.pC->seekResult = u.bg.res;








  break;
}

/* Opcode: Sequence P1 P2 * * *
** Synopsis: r[P2]=rowid
**
** Find the next available sequence number for cursor P1.

#endif /* local variables moved into u.bp */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bp.pC = p->apCsr[pOp->p1];
  assert( u.bp.pC!=0 );
  u.bp.pCrsr = u.bp.pC->pCursor;
  u.bp.res = 0;
  assert( u.bp.pCrsr!=0 );
  rc = sqlite3BtreeLast(u.bp.pCrsr, &u.bp.res);

  u.bp.pC->nullRow = (u8)u.bp.res;
  u.bp.pC->deferredMoveto = 0;
  u.bp.pC->rowidIsValid = 0;
  u.bp.pC->cacheStatus = CACHE_STALE;
  if( pOp->p2>0 && u.bp.res ){
    pc = pOp->p2 - 1;
  }

  u.bs.pC = p->apCsr[pOp->p1];
  assert( u.bs.pC!=0 );
  assert( u.bs.pC->isSorter==(pOp->opcode==OP_SorterInsert) );
  pIn2 = &aMem[pOp->p2];
  assert( pIn2->flags & MEM_Blob );
  u.bs.pCrsr = u.bs.pC->pCursor;
  if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
  assert( u.bs.pCrsr!=0 );
  assert( u.bs.pC->isTable==0 );
  rc = ExpandBlob(pIn2);
  if( rc==SQLITE_OK ){
    if( isSorter(u.bs.pC) ){
      rc = sqlite3VdbeSorterWrite(db, u.bs.pC, pIn2);
    }else{
      u.bs.nKey = pIn2->n;
      u.bs.zKey = pIn2->z;
      rc = sqlite3BtreeInsert(u.bs.pCrsr, u.bs.zKey, u.bs.nKey, "", 0, 0, pOp->p3,
          ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bs.pC->seekResult : 0)
          );
      assert( u.bs.pC->deferredMoveto==0 );
      u.bs.pC->cacheStatus = CACHE_STALE;

    }
  }
  break;
}

/* Opcode: IdxDelete P1 P2 P3 * *
** Synopsis: key=r[P2@P3]
**
** The content of P3 registers starting at register P2 form
** an unpacked index key. This opcode removes that entry from the 
** index opened by cursor P1.
*/
case OP_IdxDelete: {
#if 0  /* local variables moved into u.bt */
  VdbeCursor *pC;
  BtCursor *pCrsr;
  int res;
  UnpackedRecord r;
#endif /* local variables moved into u.bt */

  assert( pOp->p3>0 );
  assert( pOp->p2>0 && pOp->p2+pOp->p3<=(p->nMem-p->nCursor)+1 );
  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bt.pC = p->apCsr[pOp->p1];
  assert( u.bt.pC!=0 );
  u.bt.pCrsr = u.bt.pC->pCursor;

  assert( u.bt.pCrsr!=0 );
  assert( pOp->p5==0 );
  u.bt.r.pKeyInfo = u.bt.pC->pKeyInfo;
  u.bt.r.nField = (u16)pOp->p3;
  u.bt.r.flags = UNPACKED_PREFIX_MATCH;
  u.bt.r.aMem = &aMem[pOp->p2];
#ifdef SQLITE_DEBUG
  { int i; for(i=0; i<u.bt.r.nField; i++) assert( memIsValid(&u.bt.r.aMem[i]) ); }
#endif
  rc = sqlite3BtreeMovetoUnpacked(u.bt.pCrsr, &u.bt.r, 0, 0, &u.bt.res);
  if( rc==SQLITE_OK && u.bt.res==0 ){
    rc = sqlite3BtreeDelete(u.bt.pCrsr);
  }
  assert( u.bt.pC->deferredMoveto==0 );
  u.bt.pC->cacheStatus = CACHE_STALE;

  break;
}

/* Opcode: IdxRowid P1 P2 * * *
** Synopsis: r[P2]=rowid
**
** Write into register P2 an integer which is the last entry in the record at

  i64 rowid;
#endif /* local variables moved into u.bu */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bu.pC = p->apCsr[pOp->p1];
  assert( u.bu.pC!=0 );
  u.bu.pCrsr = u.bu.pC->pCursor;
  assert( u.bu.pCrsr!=0 );
  pOut->flags = MEM_Null;

  rc = sqlite3VdbeCursorMoveto(u.bu.pC);
  if( NEVER(rc) ) goto abort_due_to_error;
  assert( u.bu.pC->deferredMoveto==0 );
  assert( u.bu.pC->isTable==0 );
  if( !u.bu.pC->nullRow ){
    rc = sqlite3VdbeIdxRowid(db, u.bu.pCrsr, &u.bu.rowid);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    pOut->u.i = u.bu.rowid;
    pOut->flags = MEM_Int;

  }
  break;
}

/* Opcode: IdxGE P1 P2 P3 P4 P5
** Synopsis: key=r[P3@P4]
**

  UnpackedRecord r;
#endif /* local variables moved into u.bv */

  assert( pOp->p1>=0 && pOp->p1<p->nCursor );
  u.bv.pC = p->apCsr[pOp->p1];
  assert( u.bv.pC!=0 );
  assert( u.bv.pC->isOrdered );
  assert( u.bv.pC->pCursor!=0);
  assert( u.bv.pC->deferredMoveto==0 );
  assert( pOp->p5==0 || pOp->p5==1 );
  assert( pOp->p4type==P4_INT32 );
  u.bv.r.pKeyInfo = u.bv.pC->pKeyInfo;
  u.bv.r.nField = (u16)pOp->p4.i;
  if( pOp->p5 ){
    u.bv.r.flags = UNPACKED_INCRKEY | UNPACKED_PREFIX_MATCH;
  }else{
    u.bv.r.flags = UNPACKED_PREFIX_MATCH;
  }
  u.bv.r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
  { int i; for(i=0; i<u.bv.r.nField; i++) assert( memIsValid(&u.bv.r.aMem[i]) ); }
#endif
  rc = sqlite3VdbeIdxKeyCompare(u.bv.pC, &u.bv.r, &u.bv.res);
  if( pOp->opcode==OP_IdxLT ){
    u.bv.res = -u.bv.res;
  }else{
    assert( pOp->opcode==OP_IdxGE );
    u.bv.res++;
  }
  if( u.bv.res>0 ){
    pc = pOp->p2 - 1 ;

  }
  break;
}

/* Opcode: Destroy P1 P2 P3 * *
**
** Delete an entire database table or index whose root page in the database

    }else{
      pKey = sqlite3KeyInfoAlloc(pParse->db, nCol, 0);
    }
    if( pKey ){
      assert( sqlite3KeyInfoIsWriteable(pKey) );
      for(i=0; i<nCol; i++){
        char *zColl = pIdx->azColl[i];
        if( NEVER(zColl==0) ) zColl = "BINARY";
        pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl);
        pKey->aSortOrder[i] = pIdx->aSortOrder[i];
      }
      if( pParse->nErr ){
        sqlite3KeyInfoUnref(pKey);
      }else{
        pIdx->pKeyInfo = pKey;

    if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField);
  }
  if( ipkTop ){
    sqlite3VdbeAddOp2(v, OP_Goto, 0, ipkTop+1);
    sqlite3VdbeJumpHere(v, ipkBottom);
  }
  

  *pbMayReplace = seenReplace;

  VdbeModuleComment((v, "END: GenCnstCks(%d)", seenReplace));
}

/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite3GenerateConstraintChecks.
** A consecutive range of registers starting at regNewData contains the

    if( aRegIdx[i]==0 ) continue;
    if( pIdx->pPartIdxWhere ){
      sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2);
    }
    sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i]);
    pik_flags = 0;
    if( useSeekResult ) pik_flags = OPFLAG_USESEEKRESULT;
    if( pIdx->autoIndex==2 && !HasRowid(pTab) ){
      assert( pParse->nested==0 );
      pik_flags |= OPFLAG_NCHANGE;
    }
    if( pik_flags )  sqlite3VdbeChangeP5(v, pik_flags);
  }
  if( !HasRowid(pTab) ) return;
  regData = regNewData + 1;
  regRec = sqlite3GetTempReg(pParse);

        }
      }
    }
    for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
      int iThisCur = iIdxCur+i;
      assert( aRegIdx );
      if( (openAll || aRegIdx[i]>0)

       && iThisCur!=aiCurOnePass[1]
      ){
        assert( iThisCur!=aiCurOnePass[0] );
        sqlite3VdbeAddOp3(v, OP_OpenWrite, iThisCur, pIdx->tnum, iDb);
        sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
        assert( pParse->nTab>iThisCur );
        VdbeComment((v, "%s", pIdx->zName));
        if( okOnePass && pPk && iThisCur==iDataCur ){
          sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak,
                               regKey, nKey);

       p->aConstraintUsage[i].argvIndex,
       p->aConstraintUsage[i].omit);
  }
  sqlite3DebugPrintf("  idxNum=%d\n", p->idxNum);
  sqlite3DebugPrintf("  idxStr=%s\n", p->idxStr);
  sqlite3DebugPrintf("  orderByConsumed=%d\n", p->orderByConsumed);
  sqlite3DebugPrintf("  estimatedCost=%g\n", p->estimatedCost);
  sqlite3DebugPrintf("  estimatedRows=%lld\n", p->estimatedRows);
}
#else
#define TRACE_IDX_INPUTS(A)
#define TRACE_IDX_OUTPUTS(A)
#endif

#ifndef SQLITE_OMIT_AUTOMATIC_INDEX

    memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
    if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
    pIdxInfo->idxStr = 0;
    pIdxInfo->idxNum = 0;
    pIdxInfo->needToFreeIdxStr = 0;
    pIdxInfo->orderByConsumed = 0;
    pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
    pIdxInfo->estimatedRows = 25;
    rc = vtabBestIndex(pParse, pTab, pIdxInfo);
    if( rc ) goto whereLoopAddVtab_exit;
    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
    pNew->prereq = 0;
    mxTerm = -1;
    assert( pNew->nLSlot>=nConstraint );
    for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;

      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
                                     && pIdxInfo->orderByConsumed);
      pNew->rSetup = 0;
      pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);

      pNew->nOut = sqlite3LogEst(pIdxInfo->estimatedRows);
      whereLoopInsert(pBuilder, pNew);
      if( pNew->u.vtab.needFree ){
        sqlite3_free(pNew->u.vtab.idxStr);
        pNew->u.vtab.needFree = 0;
      }
    }
  }  

    }else{
      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
    }
    if( pLoop->wsFlags & WHERE_INDEXED ){
      Index *pIx = pLoop->u.btree.pIndex;
      int iIndexCur;
      int op = OP_OpenRead;
      /* iIdxCur is always set if to a positive value if ONEPASS is possible */
      assert( iIdxCur!=0 || (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 );
      if( pWInfo->okOnePass ){
        Index *pJ = pTabItem->pTab->pIndex;
        iIndexCur = iIdxCur;
        assert( wctrlFlags & WHERE_ONEPASS_DESIRED );
        while( ALWAYS(pJ) && pJ!=pIx ){
          iIndexCur++;
          pJ = pJ->pNext;
        }

/* Size of hash table Rtree.aHash. This hash table is not expected to
** ever contain very many entries, so a fixed number of buckets is 
** used.
*/
#define HASHSIZE 128

/* The xBestIndex method of this virtual table requires an estimate of
** the number of rows in the virtual table to calculate the costs of
** various strategies. If possible, this estimate is loaded from the
** sqlite_stat1 table (with RTREE_MIN_ROWEST as a hard-coded minimum).
** Otherwise, if no sqlite_stat1 entry is available, use 
** RTREE_DEFAULT_ROWEST.
*/
#define RTREE_DEFAULT_ROWEST 1048576
#define RTREE_MIN_ROWEST         100

/* 
** An rtree virtual-table object.
*/
struct Rtree {
  sqlite3_vtab base;
  sqlite3 *db;                /* Host database connection */
  int iNodeSize;              /* Size in bytes of each node in the node table */
  int nDim;                   /* Number of dimensions */
  int nBytesPerCell;          /* Bytes consumed per cell */
  int iDepth;                 /* Current depth of the r-tree structure */
  char *zDb;                  /* Name of database containing r-tree table */
  char *zName;                /* Name of r-tree table */ 
  RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */ 
  int nBusy;                  /* Current number of users of this structure */
  i64 nRowEst;                /* Estimated number of rows in this table */

  /* List of nodes removed during a CondenseTree operation. List is
  ** linked together via the pointer normally used for hash chains -
  ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree 
  ** headed by the node (leaf nodes have RtreeNode.iNode==0).
  */
  RtreeNode *pDeleted;

      assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCell<NCELL(pCsr->pNode) );
    }
  }

  rtreeRelease(pRtree);
  return rc;
}

/*
** Set the pIdxInfo->estimatedRows variable to nRow. Unless this
** extension is currently being used by a version of SQLite too old to
** support estimatedRows. In that case this function is a no-op.
*/
static void setEstimatedRows(sqlite3_index_info *pIdxInfo, i64 nRow){
#if SQLITE_VERSION_NUMBER>=3008002
  if( sqlite3_libversion_number()>=3008002 ){
    pIdxInfo->estimatedRows = nRow;
  }
#endif
}

/*
** Rtree virtual table module xBestIndex method. There are three
** table scan strategies to choose from (in order from most to 
** least desirable):
**
**   idxNum     idxStr        Strategy

**   ----------------------
**
** The second of each pair of bytes identifies the coordinate column
** to which the constraint applies. The leftmost coordinate column
** is 'a', the second from the left 'b' etc.
*/
static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  Rtree *pRtree = (Rtree*)tab;
  int rc = SQLITE_OK;
  int ii;
  i64 nRow;                       /* Estimated rows returned by this scan */

  int iIdx = 0;
  char zIdxStr[RTREE_MAX_DIMENSIONS*8+1];
  memset(zIdxStr, 0, sizeof(zIdxStr));


  assert( pIdxInfo->idxStr==0 );
  for(ii=0; ii<pIdxInfo->nConstraint && iIdx<(int)(sizeof(zIdxStr)-1); ii++){
    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[ii];

    if( p->usable && p->iColumn==0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
      /* We have an equality constraint on the rowid. Use strategy 1. */
      int jj;
      for(jj=0; jj<ii; jj++){
        pIdxInfo->aConstraintUsage[jj].argvIndex = 0;
        pIdxInfo->aConstraintUsage[jj].omit = 0;
      }
      pIdxInfo->idxNum = 1;
      pIdxInfo->aConstraintUsage[ii].argvIndex = 1;
      pIdxInfo->aConstraintUsage[jj].omit = 1;

      /* This strategy involves a two rowid lookups on an B-Tree structures
      ** and then a linear search of an R-Tree node. This should be 
      ** considered almost as quick as a direct rowid lookup (for which 
      ** sqlite uses an internal cost of 0.0). It is expected to return
      ** a single row.
      */ 
      pIdxInfo->estimatedCost = 30.0;
      setEstimatedRows(pIdxInfo, 1);
      return SQLITE_OK;
    }

    if( p->usable && (p->iColumn>0 || p->op==SQLITE_INDEX_CONSTRAINT_MATCH) ){
      u8 op;
      switch( p->op ){
        case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;

  }

  pIdxInfo->idxNum = 2;
  pIdxInfo->needToFreeIdxStr = 1;
  if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){
    return SQLITE_NOMEM;
  }

  nRow = pRtree->nRowEst / (iIdx + 1);
  pIdxInfo->estimatedCost = (double)6.0 * (double)nRow;
  setEstimatedRows(pIdxInfo, nRow);

  return rc;
}

/*
** Return the N-dimensional volumn of the cell stored in *p.
*/
static RtreeDValue cellArea(Rtree *pRtree, RtreeCell *p){

  );
  if( zSql ){
    rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }
  return rc;
}

/*
** This function populates the pRtree->nRowEst variable with an estimate
** of the number of rows in the virtual table. If possible, this is based
** on sqlite_stat1 data. Otherwise, use RTREE_DEFAULT_ROWEST.
*/
static int rtreeQueryStat1(sqlite3 *db, Rtree *pRtree){
  const char *zSql = "SELECT stat FROM sqlite_stat1 WHERE tbl= ? || '_rowid'";
  sqlite3_stmt *p;
  int rc;
  i64 nRow = 0;

  rc = sqlite3_prepare_v2(db, zSql, -1, &p, 0);
  if( rc==SQLITE_OK ){
    sqlite3_bind_text(p, 1, pRtree->zName, -1, SQLITE_STATIC);
    if( sqlite3_step(p)==SQLITE_ROW ) nRow = sqlite3_column_int64(p, 0);
    rc = sqlite3_finalize(p);
  }else if( rc!=SQLITE_NOMEM ){
    rc = SQLITE_OK;
  }

  if( rc==SQLITE_OK ){
    if( nRow==0 ){
      pRtree->nRowEst = RTREE_DEFAULT_ROWEST;
    }else{
      pRtree->nRowEst = MAX(nRow, RTREE_MIN_ROWEST);
    }
  }

  return rc;
}

static sqlite3_module rtreeModule = {
  0,                          /* iVersion */
  rtreeCreate,                /* xCreate - create a table */
  rtreeConnect,               /* xConnect - connect to an existing table */
  rtreeBestIndex,             /* xBestIndex - Determine search strategy */
  rtreeDisconnect,            /* xDisconnect - Disconnect from a table */

  appStmt[3] = &pRtree->pReadRowid;
  appStmt[4] = &pRtree->pWriteRowid;
  appStmt[5] = &pRtree->pDeleteRowid;
  appStmt[6] = &pRtree->pReadParent;
  appStmt[7] = &pRtree->pWriteParent;
  appStmt[8] = &pRtree->pDeleteParent;

  rc = rtreeQueryStat1(db, pRtree);
  for(i=0; i<N_STATEMENT && rc==SQLITE_OK; i++){
    char *zSql = sqlite3_mprintf(azSql[i], zDb, zPrefix);
    if( zSql ){
      rc = sqlite3_prepare_v2(db, zSql, -1, appStmt[i], 0); 
    }else{
      rc = SQLITE_NOMEM;
    }

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.8.2"
#define SQLITE_VERSION_NUMBER 3008002
#define SQLITE_SOURCE_ID      "2013-11-11 19:56:35 f58d57017199421167dae8ebc67db2f19be45082"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version, sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

** ^[sqlite3_free()] is used to free idxPtr if and only if
** needToFreeIdxPtr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of a particular
** strategy. A cost of N indicates that the cost of the strategy is similar
** to a linear scan of an SQLite table with N rows. A cost of log(N) 
** indicates that the expense of the operation is similar to that of a
** binary search on a unique indexed field of an SQLite table with N rows.
**
** ^The estimatedRows value is an estimate of the number of rows that
** will be returned by the strategy.
**
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
** structure for SQLite version 3.8.2. If a virtual table extension is
** used with an SQLite version earlier than 3.8.2, the results of attempting 
** to read or write the estimatedRows field are undefined (but are likely 
** to included crashing the application). The estimatedRows field should
** therefore only be used if [sqlite3_libversion_number()] returns a
** value greater than or equal to 3008002.
*/
struct sqlite3_index_info {
  /* Inputs */
  int nConstraint;           /* Number of entries in aConstraint */
  struct sqlite3_index_constraint {
     int iColumn;              /* Column on left-hand side of constraint */
     unsigned char op;         /* Constraint operator */

    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
    unsigned char omit;      /* Do not code a test for this constraint */
  } *aConstraintUsage;
  int idxNum;                /* Number used to identify the index */
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;           /* Estimated cost of using this index */
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
};

/*
** CAPI3REF: Virtual Table Constraint Operator Codes
**
** These macros defined the allowed values for the
** [sqlite3_index_info].aConstraint[].op field.  Each value represents

        {
            constraintUsages = new SQLiteIndexConstraintUsage[nConstraint];
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Determines if the native estimatedRows field can be used, based on
        /// the available version of the SQLite core library.
        /// </summary>
        /// <returns>
        /// Non-zero if the <see cref="EstimatedRows" /> property is supported
        /// by the SQLite core library.
        /// </returns>
        public bool CanUseEstimatedRows()
        {
            if (UnsafeNativeMethods.sqlite3_libversion_number() >= 3008002)
                return true;

            return false;
        }

        ///////////////////////////////////////////////////////////////////////

        #region Public Properties
        private SQLiteIndexConstraintUsage[] constraintUsages;
        /// <summary>
        /// An array of <see cref="SQLiteIndexConstraintUsage" /> object
        /// instances, each containing information to be supplied to the SQLite
        /// core library.
        /// </summary>

        /// indicates that a default estimated cost value should be used.
        /// </summary>
        public double? EstimatedCost
        {
            get { return estimatedCost; }
            set { estimatedCost = value; }
        }

        ///////////////////////////////////////////////////////////////////////

        private long? estimatedRows;
        /// <summary>
        /// Estimated number of rows returned.  Using a null value here
        /// indicates that a default estimated rows value should be used.
        /// </summary>
        public long? EstimatedRows
        {
            get { return estimatedRows; }
            set { estimatedRows = value; }
        }
        #endregion
    }
    #endregion

    ///////////////////////////////////////////////////////////////////////////

    #region SQLiteIndex Helper Class
    /// <summary>
    /// This class represents the various inputs and outputs used with the
    /// <see cref="ISQLiteManagedModule.BestIndex" /> method.
    /// </summary>
    public sealed class SQLiteIndex
    {










        #region Internal Constructors
        /// <summary>
        /// Constructs an instance of this class.
        /// </summary>
        /// <param name="nConstraint">
        /// The number of <see cref="SQLiteIndexConstraint" /> (and
        /// <see cref="SQLiteIndexConstraintUsage" />) instances to

            SQLiteMarshal.WriteInt32(pIndex, offset,
                index.Outputs.OrderByConsumed);

            offset = SQLiteMarshal.NextOffsetOf(offset, sizeof(int),
                sizeof(double));

            if (index.Outputs.EstimatedCost.HasValue)
            {
                SQLiteMarshal.WriteDouble(pIndex, offset,
                    index.Outputs.EstimatedCost.GetValueOrDefault());
            }

            if (index.Outputs.CanUseEstimatedRows() &&
                index.Outputs.EstimatedRows.HasValue)
            {
                SQLiteMarshal.WriteInt64(pIndex, offset,
                    index.Outputs.EstimatedRows.GetValueOrDefault());
            }
        }
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Public Properties
        private SQLiteIndexInputs inputs;

#else
            Marshal.WriteInt32(IntPtrForOffset(pointer, offset), value);
#endif
        }

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Writes an <see cref="Int64" /> value to the specified memory
        /// location.
        /// </summary>
        /// <param name="pointer">
        /// The <see cref="IntPtr" /> object instance representing the base
        /// memory location.
        /// </param>
        /// <param name="offset">
        /// The integer offset from the base memory location where the
        /// <see cref="Int64" /> value to be written is located.
        /// </param>
        /// <param name="value">
        /// The <see cref="Int64" /> value to write.
        /// </param>
        public static void WriteInt64(
            IntPtr pointer,
            int offset,
            long value
            )
        {
#if !PLATFORM_COMPACTFRAMEWORK
            Marshal.WriteInt64(pointer, offset, value);
#else
            Marshal.WriteInt64(IntPtrForOffset(pointer, offset), value);
#endif
        }

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Writes a <see cref="Double" /> value to the specified memory
        /// location.
        /// </summary>
        /// <param name="pointer">
        /// The <see cref="IntPtr" /> object instance representing the base
        /// memory location.

        /// Modifies the specified <see cref="SQLiteIndex" /> object instance
        /// to contain the specified estimated cost.
        /// </summary>
        /// <param name="index">
        /// The <see cref="SQLiteIndex" /> object instance to modify.
        /// </param>
        /// <param name="estimatedCost">
        /// The estimated cost value to use.  Using a null value means that the
        /// default value provided by the SQLite core library should be used.
        /// </param>
        /// <returns>
        /// Non-zero upon success.
        /// </returns>
        protected virtual bool SetEstimatedCost(
            SQLiteIndex index,
            double? estimatedCost
            )
        {
            if ((index == null) || (index.Outputs == null))
                return false;

            index.Outputs.EstimatedCost = estimatedCost;
            return true;

        /// <returns>
        /// Non-zero upon success.
        /// </returns>
        protected virtual bool SetEstimatedCost(
            SQLiteIndex index
            )
        {
            return SetEstimatedCost(index, null);
        }

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Modifies the specified <see cref="SQLiteIndex" /> object instance
        /// to contain the specified estimated rows.
        /// </summary>
        /// <param name="index">
        /// The <see cref="SQLiteIndex" /> object instance to modify.
        /// </param>
        /// <param name="estimatedRows">
        /// The estimated rows value to use.  Using a null value means that the
        /// default value provided by the SQLite core library should be used.
        /// </param>
        /// <returns>
        /// Non-zero upon success.
        /// </returns>
        protected virtual bool SetEstimatedRows(
            SQLiteIndex index,
            long? estimatedRows
            )
        {
            if ((index == null) || (index.Outputs == null))
                return false;

            index.Outputs.EstimatedRows = estimatedRows;
            return true;
        }

        ///////////////////////////////////////////////////////////////////////

        /// <summary>
        /// Modifies the specified <see cref="SQLiteIndex" /> object instance
        /// to contain the default estimated rows.
        /// </summary>
        /// <param name="index">
        /// The <see cref="SQLiteIndex" /> object instance to modify.
        /// </param>
        /// <returns>
        /// Non-zero upon success.
        /// </returns>
        protected virtual bool SetEstimatedRows(
            SQLiteIndex index
            )
        {
            return SetEstimatedRows(index, null);
        }
        #endregion
        #endregion

        ///////////////////////////////////////////////////////////////////////

        #region Public Properties