SQLite

  Fts3Expr *pFree = 0;            /* List of free nodes. Linked by pParent. */
  int eType = pRoot->eType;       /* Type of node in this tree */

  if( nMaxDepth==0 ){
    rc = SQLITE_ERROR;
  }

  if( rc==SQLITE_OK ){
    if( (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
      Fts3Expr **apLeaf;
      apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
      if( 0==apLeaf ){
        rc = SQLITE_NOMEM;
      }else{
        memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
      }

      if( rc==SQLITE_OK ){
        int i;
        Fts3Expr *p;

        /* Set $p to point to the left-most leaf in the tree of eType nodes. */
        for(p=pRoot; p->eType==eType; p=p->pLeft){
          assert( p->pParent==0 || p->pParent->pLeft==p );
          assert( p->pLeft && p->pRight );
        }

        /* This loop runs once for each leaf in the tree of eType nodes. */
        while( 1 ){
          int iLvl;
          Fts3Expr *pParent = p->pParent;     /* Current parent of p */

          assert( pParent==0 || pParent->pLeft==p );
          p->pParent = 0;
          if( pParent ){
            pParent->pLeft = 0;
          }else{
            pRoot = 0;
          }
          rc = fts3ExprBalance(&p, nMaxDepth-1);
          if( rc!=SQLITE_OK ) break;

          for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
            if( apLeaf[iLvl]==0 ){
              apLeaf[iLvl] = p;
              p = 0;
            }else{
              assert( pFree );
              pFree->pLeft = apLeaf[iLvl];
              pFree->pRight = p;
















































              pFree->pLeft->pParent = pFree;
              pFree->pRight->pParent = pFree;

              p = pFree;
              pFree = pFree->pParent;
              p->pParent = 0;
              apLeaf[iLvl] = 0;
            }
          }
          if( p ){
            sqlite3Fts3ExprFree(p);
            rc = SQLITE_TOOBIG;
            break;
          }

          /* If that was the last leaf node, break out of the loop */
          if( pParent==0 ) break;

          /* Set $p to point to the next leaf in the tree of eType nodes */
          for(p=pParent->pRight; p->eType==eType; p=p->pLeft);

          /* Remove pParent from the original tree. */
          assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
          pParent->pRight->pParent = pParent->pParent;
          if( pParent->pParent ){
            pParent->pParent->pLeft = pParent->pRight;
          }else{
            assert( pParent==pRoot );
            pRoot = pParent->pRight;
          }

          /* Link pParent into the free node list. It will be used as an
          ** internal node of the new tree.  */
          pParent->pParent = pFree;
          pFree = pParent;
        }

        if( rc==SQLITE_OK ){
          p = 0;
          for(i=0; i<nMaxDepth; i++){
            if( apLeaf[i] ){
              if( p==0 ){
                p = apLeaf[i];
                p->pParent = 0;
              }else{
                assert( pFree!=0 );
                pFree->pRight = p;
                pFree->pLeft = apLeaf[i];
                pFree->pLeft->pParent = pFree;
                pFree->pRight->pParent = pFree;

                p = pFree;
                pFree = pFree->pParent;
                p->pParent = 0;
              }
            }
          }
          pRoot = p;
        }else{
          /* An error occurred. Delete the contents of the apLeaf[] array 
          ** and pFree list. Everything else is cleaned up by the call to
          ** sqlite3Fts3ExprFree(pRoot) below.  */
          Fts3Expr *pDel;
          for(i=0; i<nMaxDepth; i++){
            sqlite3Fts3ExprFree(apLeaf[i]);
          }
          while( (pDel=pFree)!=0 ){
            pFree = pDel->pParent;
            sqlite3_free(pDel);
          }
        }

        assert( pFree==0 );
        sqlite3_free( apLeaf );
      }
    }else if( eType==FTSQUERY_NOT ){
      Fts3Expr *pLeft = pRoot->pLeft;
      Fts3Expr *pRight = pRoot->pRight;

      pRoot->pLeft = 0;
      pRoot->pRight = 0;
      pLeft->pParent = 0;
      pRight->pParent = 0;

      rc = fts3ExprBalance(&pLeft, nMaxDepth-1);
      if( rc==SQLITE_OK ){
        rc = fts3ExprBalance(&pRight, nMaxDepth-1);
      }

      if( rc!=SQLITE_OK ){
        sqlite3Fts3ExprFree(pRight);
        sqlite3Fts3ExprFree(pLeft);
      }else{
        assert( pLeft && pRight );
        pRoot->pLeft = pLeft;
        pLeft->pParent = pRoot;
        pRoot->pRight = pRight;
        pRight->pParent = pRoot;
      }
    }
  }
  
  if( rc!=SQLITE_OK ){
    sqlite3Fts3ExprFree(pRoot);
    pRoot = 0;
  }
  *pp = pRoot;
  return rc;
}

    pNext = &pReader->aDoclist[pReader->nDoclist];
  }

  if( !pNext || pNext>=&pReader->aNode[pReader->nNode] ){

    if( fts3SegReaderIsPending(pReader) ){
      Fts3HashElem *pElem = *(pReader->ppNextElem);
      sqlite3_free(pReader->aNode);
      pReader->aNode = 0;
      if( pElem ){
        char *aCopy;
        PendingList *pList = (PendingList *)fts3HashData(pElem);
        int nCopy = pList->nData+1;
        pReader->zTerm = (char *)fts3HashKey(pElem);
        pReader->nTerm = fts3HashKeysize(pElem);
        aCopy = (char*)sqlite3_malloc(nCopy);
        if( !aCopy ) return SQLITE_NOMEM;
        memcpy(aCopy, pList->aData, nCopy);
        pReader->nNode = pReader->nDoclist = nCopy;
        pReader->aNode = pReader->aDoclist = aCopy;
        pReader->ppNextElem++;
        assert( pReader->aNode );
      }
      return SQLITE_OK;
    }

    fts3SegReaderSetEof(pReader);

}

/*
** Free all allocations associated with the iterator passed as the 
** second argument.
*/
void sqlite3Fts3SegReaderFree(Fts3SegReader *pReader){
  if( pReader ){
    if( !fts3SegReaderIsPending(pReader) ){
      sqlite3_free(pReader->zTerm);
    }
    if( !fts3SegReaderIsRootOnly(pReader) ){
      sqlite3_free(pReader->aNode);

    }
    sqlite3_blob_close(pReader->pBlob);
  }
  sqlite3_free(pReader);
}

/*
** Allocate a new SegReader object.
*/

extern int sqlite3_fts5_may_be_corrupt;
# define assert_nc(x) assert(sqlite3_fts5_may_be_corrupt || (x))
#else
# define assert_nc(x) assert(x)
#endif

typedef struct Fts5Global Fts5Global;
typedef struct Fts5Colset Fts5Colset;

/* If a NEAR() clump or phrase may only match a specific set of columns, 
** then an object of the following type is used to record the set of columns.
** Each entry in the aiCol[] array is a column that may be matched.
**
** This object is used by fts5_expr.c and fts5_index.c.
*/
struct Fts5Colset {
  int nCol;
  int aiCol[1];
};



/**************************************************************************
** Interface to code in fts5_config.c. fts5_config.c contains contains code
** to parse the arguments passed to the CREATE VIRTUAL TABLE statement.
*/

typedef struct Fts5Config Fts5Config;

** Create/destroy an Fts5Index object.
*/
int sqlite3Fts5IndexOpen(Fts5Config *pConfig, int bCreate, Fts5Index**, char**);
int sqlite3Fts5IndexClose(Fts5Index *p);

/*
** for(
**   sqlite3Fts5IndexQuery(p, "token", 5, 0, 0, &pIter);
**   0==sqlite3Fts5IterEof(pIter);
**   sqlite3Fts5IterNext(pIter)
** ){
**   i64 iRowid = sqlite3Fts5IterRowid(pIter);
** }
*/

/*
** Open a new iterator to iterate though all rowids that match the 
** specified token or token prefix.
*/
int sqlite3Fts5IndexQuery(
  Fts5Index *p,                   /* FTS index to query */
  const char *pToken, int nToken, /* Token (or prefix) to query for */
  int flags,                      /* Mask of FTS5INDEX_QUERY_X flags */
  Fts5Colset *pColset,            /* Match these columns only */
  Fts5IndexIter **ppIter          /* OUT: New iterator object */
);

/*
** The various operations on open token or token prefix iterators opened
** using sqlite3Fts5IndexQuery().
*/
int sqlite3Fts5IterEof(Fts5IndexIter*);

/*
** Indicate that subsequent calls to sqlite3Fts5IndexWrite() pertain to
** document iDocid.
*/
int sqlite3Fts5IndexBeginWrite(
  Fts5Index *p,                   /* Index to write to */
  int bDelete,                    /* True if current operation is a delete */
  i64 iDocid                      /* Docid to add or remove data from */
);

/*
** Flush any data stored in the in-memory hash tables to the database.
** If the bCommit flag is true, also close any open blob handles.
*/

int sqlite3Fts5GetVarint32(const unsigned char *p, u32 *v);
int sqlite3Fts5GetVarintLen(u32 iVal);
u8 sqlite3Fts5GetVarint(const unsigned char*, u64*);
int sqlite3Fts5PutVarint(unsigned char *p, u64 v);

#define fts5GetVarint32(a,b) sqlite3Fts5GetVarint32(a,(u32*)&b)
#define fts5GetVarint    sqlite3Fts5GetVarint

#define fts5FastGetVarint32(a, iOff, nVal) {      \
  nVal = (a)[iOff++];                             \
  if( nVal & 0x80 ){                              \
    iOff--;                                       \
    iOff += fts5GetVarint32(&(a)[iOff], nVal);    \
  }                                               \
}


/*
** End of interface to code in fts5_varint.c.
**************************************************************************/


/**************************************************************************

int sqlite3Fts5StorageClose(Fts5Storage *p);
int sqlite3Fts5StorageRename(Fts5Storage*, const char *zName);

int sqlite3Fts5DropAll(Fts5Config*);
int sqlite3Fts5CreateTable(Fts5Config*, const char*, const char*, int, char **);

int sqlite3Fts5StorageDelete(Fts5Storage *p, i64);
int sqlite3Fts5StorageContentInsert(Fts5Storage *p, sqlite3_value**, i64*);
int sqlite3Fts5StorageIndexInsert(Fts5Storage *p, sqlite3_value**, i64);

int sqlite3Fts5StorageIntegrity(Fts5Storage *p);

int sqlite3Fts5StorageStmt(Fts5Storage *p, int eStmt, sqlite3_stmt**, char**);
void sqlite3Fts5StorageStmtRelease(Fts5Storage *p, int eStmt, sqlite3_stmt*);

int sqlite3Fts5StorageDocsize(Fts5Storage *p, i64 iRowid, int *aCol);

*/
typedef struct Fts5Expr Fts5Expr;
typedef struct Fts5ExprNode Fts5ExprNode;
typedef struct Fts5Parse Fts5Parse;
typedef struct Fts5Token Fts5Token;
typedef struct Fts5ExprPhrase Fts5ExprPhrase;
typedef struct Fts5ExprNearset Fts5ExprNearset;


struct Fts5Token {
  const char *p;                  /* Token text (not NULL terminated) */
  int n;                          /* Size of buffer p in bytes */
};

/* Parse a MATCH expression. */

Fts5ExprNearset *sqlite3Fts5ParseNearset(
  Fts5Parse*, 
  Fts5ExprNearset*,
  Fts5ExprPhrase* 
);

Fts5Colset *sqlite3Fts5ParseColset(
  Fts5Parse*, 
  Fts5Colset*, 
  Fts5Token *
);

void sqlite3Fts5ParsePhraseFree(Fts5ExprPhrase*);
void sqlite3Fts5ParseNearsetFree(Fts5ExprNearset*);
void sqlite3Fts5ParseNodeFree(Fts5ExprNode*);

void sqlite3Fts5ParseSetDistance(Fts5Parse*, Fts5ExprNearset*, Fts5Token*);
void sqlite3Fts5ParseSetColset(Fts5Parse*, Fts5ExprNearset*, Fts5Colset*);
void sqlite3Fts5ParseFinished(Fts5Parse *pParse, Fts5ExprNode *p);
void sqlite3Fts5ParseNear(Fts5Parse *pParse, Fts5Token*);

/*
** End of interface to code in fts5_expr.c.
**************************************************************************/

  if( i>=n ){
    /* EOF */
    *piOff = -1;
    return 1;  
  }else{
    i64 iOff = *piOff;
    int iVal;
    fts5FastGetVarint32(a, i, iVal);
    if( iVal==1 ){
      fts5FastGetVarint32(a, i, iVal);
      iOff = ((i64)iVal) << 32;
      fts5FastGetVarint32(a, i, iVal);
    }
    *piOff = iOff + (iVal-2);
    *pi = i;
    return 0;
  }
}

int sqlite3Fts5PoslistWriterAppend(
  Fts5Buffer *pBuf, 
  Fts5PoslistWriter *pWriter,
  i64 iPos
){
  static const i64 colmask = ((i64)(0x7FFFFFFF)) << 32;
  int rc = SQLITE_OK;
  if( 0==sqlite3Fts5BufferGrow(&rc, pBuf, 5+5+5) ){
    if( (iPos & colmask) != (pWriter->iPrev & colmask) ){
      pBuf->p[pBuf->n++] = 1;
      pBuf->n += sqlite3Fts5PutVarint(&pBuf->p[pBuf->n], (iPos>>32));
      pWriter->iPrev = (iPos & colmask);
    }
    pBuf->n += sqlite3Fts5PutVarint(&pBuf->p[pBuf->n], (iPos-pWriter->iPrev)+2);
    pWriter->iPrev = iPos;
  }
  return rc;
}

void *sqlite3Fts5MallocZero(int *pRc, int nByte){
  void *pRet = 0;
  if( *pRc==SQLITE_OK ){
    pRet = sqlite3_malloc(nByte);

** Return true if character 't' may be part of an FTS5 bareword, or false
** otherwise. Characters that may be part of barewords:
**
**   * All non-ASCII characters,
**   * The 52 upper and lower case ASCII characters, and
**   * The 10 integer ASCII characters.
**   * The underscore character "_" (0x5F).
**   * The unicode "subsitute" character (0x1A).
*/
int sqlite3Fts5IsBareword(char t){
  u8 aBareword[128] = {
    0, 0, 0, 0, 0, 0, 0, 0,    0, 0, 0, 0, 0, 0, 0, 0,   /* 0x00 .. 0x0F */
    0, 0, 0, 0, 0, 0, 0, 0,    0, 0, 1, 0, 0, 0, 0, 0,   /* 0x10 .. 0x1F */
    0, 0, 0, 0, 0, 0, 0, 0,    0, 0, 0, 0, 0, 0, 0, 0,   /* 0x20 .. 0x2F */
    1, 1, 1, 1, 1, 1, 1, 1,    1, 1, 0, 0, 0, 0, 0, 0,   /* 0x30 .. 0x3F */
    0, 1, 1, 1, 1, 1, 1, 1,    1, 1, 1, 1, 1, 1, 1, 1,   /* 0x40 .. 0x4F */
    1, 1, 1, 1, 1, 1, 1, 1,    1, 1, 1, 0, 0, 0, 0, 1,   /* 0x50 .. 0x5F */
    0, 1, 1, 1, 1, 1, 1, 1,    1, 1, 1, 1, 1, 1, 1, 1,   /* 0x60 .. 0x6F */
    1, 1, 1, 1, 1, 1, 1, 1,    1, 1, 1, 0, 0, 0, 0, 0    /* 0x70 .. 0x7F */
  };

  return (t & 0x80) || aBareword[(int)t];
}

struct Fts5ExprPhrase {
  Fts5ExprNode *pNode;            /* FTS5_STRING node this phrase is part of */
  Fts5Buffer poslist;             /* Current position list */
  int nTerm;                      /* Number of entries in aTerm[] */
  Fts5ExprTerm aTerm[1];          /* Terms that make up this phrase */
};











/*
** One or more phrases that must appear within a certain token distance of
** each other within each matching document.
*/
struct Fts5ExprNearset {
  int nNear;                      /* NEAR parameter */
  Fts5Colset *pColset;            /* Columns to search (NULL -> all columns) */
  int nPhrase;                    /* Number of entries in aPhrase[] array */
  Fts5ExprPhrase *apPhrase[1];    /* Array of phrase pointers */
};


/*
** Parse context.

  if( p ){
    sqlite3Fts5ParseNodeFree(p->pRoot);
    sqlite3_free(p->apExprPhrase);
    sqlite3_free(p);
  }
}

static int fts5ExprColsetTest(Fts5Colset *pColset, int iCol){
  int i;
  for(i=0; i<pColset->nCol; i++){
    if( pColset->aiCol[i]==iCol ) return 1;
  }
  return 0;
}

**
** SQLITE_OK is returned if an error occurs, or an SQLite error code 
** otherwise. It is not considered an error code if the current rowid is 
** not a match.
*/
static int fts5ExprPhraseIsMatch(
  Fts5ExprNode *pNode,            /* Node pPhrase belongs to */
  Fts5Colset *pColset,            /* Restrict matches to these columns */
  Fts5ExprPhrase *pPhrase,        /* Phrase object to initialize */
  int *pbMatch                    /* OUT: Set to true if really a match */
){
  Fts5PoslistWriter writer = {0};
  Fts5PoslistReader aStatic[4];
  Fts5PoslistReader *aIter = aStatic;
  int i;

  while( p<pEnd && ((prev & 0x80) || *p!=0x01) ){
    prev = *p++;
  }
  return p - (*pa);
}

static int fts5ExprExtractColset (
  Fts5Colset *pColset,            /* Colset to filter on */
  const u8 *pPos, int nPos,       /* Position list */
  Fts5Buffer *pBuf                /* Output buffer */
){
  int rc = SQLITE_OK;
  int i;

  fts5BufferZero(pBuf);

  ** of a single term only, grab pointers into the poslist managed by the
  ** fts5_index.c iterator object. This is much faster than synthesizing 
  ** a new poslist the way we have to for more complicated phrase or NEAR
  ** expressions.  */
  Fts5ExprNearset *pNear = pNode->pNear;
  Fts5ExprPhrase *pPhrase = pNear->apPhrase[0];
  Fts5IndexIter *pIter = pPhrase->aTerm[0].pIter;
  Fts5Colset *pColset = pNear->pColset;
  const u8 *pPos;
  int nPos;
  int rc;

  assert( pNode->eType==FTS5_TERM );
  assert( pNear->nPhrase==1 && pPhrase->nTerm==1 );
  assert( pPhrase->aTerm[0].pSynonym==0 );

          sqlite3Fts5IterClose(p->pIter);
          p->pIter = 0;
        }
        rc = sqlite3Fts5IndexQuery(
            pExpr->pIndex, p->zTerm, strlen(p->zTerm),
            (pTerm->bPrefix ? FTS5INDEX_QUERY_PREFIX : 0) |
            (pExpr->bDesc ? FTS5INDEX_QUERY_DESC : 0),
            pNear->pColset,
            &p->pIter
        );
        assert( rc==SQLITE_OK || p->pIter==0 );
        if( p->pIter && 0==sqlite3Fts5IterEof(p->pIter) ){
          bEof = 0;
        }
      }

    nNear = FTS5_DEFAULT_NEARDIST;
  }
  pNear->nNear = nNear;
}

/*
** The second argument passed to this function may be NULL, or it may be
** an existing Fts5Colset object. This function returns a pointer to
** a new colset object containing the contents of (p) with new value column
** number iCol appended. 
**
** If an OOM error occurs, store an error code in pParse and return NULL.
** The old colset object (if any) is not freed in this case.
*/
static Fts5Colset *fts5ParseColset(
  Fts5Parse *pParse,              /* Store SQLITE_NOMEM here if required */
  Fts5Colset *p,                  /* Existing colset object */
  int iCol                        /* New column to add to colset object */
){
  int nCol = p ? p->nCol : 0;     /* Num. columns already in colset object */
  Fts5Colset *pNew;               /* New colset object to return */

  assert( pParse->rc==SQLITE_OK );
  assert( iCol>=0 && iCol<pParse->pConfig->nCol );

  pNew = sqlite3_realloc(p, sizeof(Fts5Colset) + sizeof(int)*nCol);
  if( pNew==0 ){
    pParse->rc = SQLITE_NOMEM;
  }else{
    int *aiCol = pNew->aiCol;
    int i, j;
    for(i=0; i<nCol; i++){
      if( aiCol[i]==iCol ) return pNew;

    for(i=1; i<pNew->nCol; i++) assert( pNew->aiCol[i]>pNew->aiCol[i-1] );
#endif
  }

  return pNew;
}

Fts5Colset *sqlite3Fts5ParseColset(
  Fts5Parse *pParse,              /* Store SQLITE_NOMEM here if required */
  Fts5Colset *pColset,            /* Existing colset object */
  Fts5Token *p
){
  Fts5Colset *pRet = 0;
  int iCol;
  char *z;                        /* Dequoted copy of token p */

  z = sqlite3Fts5Strndup(&pParse->rc, p->p, p->n);
  if( pParse->rc==SQLITE_OK ){
    Fts5Config *pConfig = pParse->pConfig;
    sqlite3Fts5Dequote(z);

  return pRet;
}

void sqlite3Fts5ParseSetColset(
  Fts5Parse *pParse, 
  Fts5ExprNearset *pNear, 
  Fts5Colset *pColset 
){
  if( pNear ){
    pNear->pColset = pColset;
  }else{
    sqlite3_free(pColset);
  }
}

  ** Variables related to the accumulation of tokens and doclists within the
  ** in-memory hash tables before they are flushed to disk.
  */
  Fts5Hash *pHash;                /* Hash table for in-memory data */
  int nMaxPendingData;            /* Max pending data before flush to disk */
  int nPendingData;               /* Current bytes of pending data */
  i64 iWriteRowid;                /* Rowid for current doc being written */
  int bDelete;                    /* Current write is a delete */

  /* Error state. */
  int rc;                         /* Current error code */

  /* State used by the fts5DataXXX() functions. */
  sqlite3_blob *pReader;          /* RO incr-blob open on %_data table */
  sqlite3_stmt *pWriter;          /* "INSERT ... %_data VALUES(?,?)" */
  sqlite3_stmt *pDeleter;         /* "DELETE FROM %_data ... id>=? AND id<=?" */
  sqlite3_stmt *pIdxWriter;       /* "INSERT ... %_idx VALUES(?,?,?,?)" */
  sqlite3_stmt *pIdxDeleter;      /* "DELETE FROM %_idx WHERE segid=? */
  sqlite3_stmt *pIdxSelect;
  int nRead;                      /* Total number of blocks read */
};

struct Fts5DoclistIter {
  u8 *aEof;                       /* Pointer to 1 byte past end of doclist */



  /* Output variables. aPoslist==0 at EOF */
  i64 iRowid;
  u8 *aPoslist;
  int nPoslist;
  int nSize;
};

/*
** The contents of the "structure" record for each index are represented
** using an Fts5Structure record in memory. Which uses instances of the 
** other Fts5StructureXXX types as components.
*/

        }else{
          pIter->pLeaf->p = (u8*)pList;
          pIter->pLeaf->nn = nList;
          pIter->pLeaf->szLeaf = nList;
          pIter->iEndofDoclist = nList+1;
          sqlite3Fts5BufferSet(&p->rc, &pIter->term, strlen(zTerm), (u8*)zTerm);
          pIter->iLeafOffset = fts5GetVarint(pList, (u64*)&pIter->iRowid);
          if( pbNewTerm ) *pbNewTerm = 1;
        }
      }else{
        iOff = 0;
        /* Next entry is not on the current page */
        while( iOff==0 ){
          fts5SegIterNextPage(p, pIter);
          pLeaf = pIter->pLeaf;

  ){
    return;
  }

  pIter->pDlidx = fts5DlidxIterInit(p, bRev, iSeg, pIter->iTermLeafPgno);
}









#define fts5IndexSkipVarint(a, iOff) {            \
  int iEnd = iOff+9;                              \
  while( (a[iOff++] & 0x80) && iOff<iEnd );       \
}

/*
** The iterator object passed as the second argument currently contains

  iPgidx = szLeaf;
  iPgidx += fts5GetVarint32(&a[iPgidx], iTermOff);
  iOff = iTermOff;

  while( 1 ){

    /* Figure out how many new bytes are in this term */
    fts5FastGetVarint32(a, iOff, nNew);
    if( nKeep<nMatch ){
      goto search_failed;
    }

    assert( nKeep>=nMatch );
    if( nKeep==nMatch ){
      int nCmp;

    }

    iPgidx += fts5GetVarint32(&a[iPgidx], nKeep);
    iTermOff += nKeep;
    iOff = iTermOff;

    /* Read the nKeep field of the next term. */
    fts5FastGetVarint32(a, iOff, nKeep);
  }

 search_failed:
  if( bGe==0 ){
    fts5DataRelease(pIter->pLeaf);
    pIter->pLeaf = 0;
    return;

      if( (ret + i) > nMax ) break;
      ret += i;
    }
  }
  return ret;
}

#define fts5BufferSafeAppendBlob(pBuf, pBlob, nBlob) {     \
  assert( (pBuf)->nSpace>=((pBuf)->n+nBlob) );             \
  memcpy(&(pBuf)->p[(pBuf)->n], pBlob, nBlob);             \
  (pBuf)->n += nBlob;                                      \
}

#define fts5BufferSafeAppendVarint(pBuf, iVal) {                \
  (pBuf)->n += sqlite3Fts5PutVarint(&(pBuf)->p[(pBuf)->n], (iVal));  \
  assert( (pBuf)->nSpace>=(pBuf)->n );                          \
}

/*
** Flush the contents of in-memory hash table iHash to a new level-0 
** segment on disk. Also update the corresponding structure record.
**
** If an error occurs, set the Fts5Index.rc error code. If an error has 

  fts5StructureRelease(pStruct);

  return fts5IndexReturn(p);
}

static void fts5PoslistCallback(
  Fts5Index *p, 
  void *pContext, 
  const u8 *pChunk, int nChunk
){
  assert_nc( nChunk>=0 );
  if( nChunk>0 ){
    fts5BufferAppendBlob(&p->rc, (Fts5Buffer*)pContext, nChunk, pChunk);
  }
}

typedef struct PoslistCallbackCtx PoslistCallbackCtx;
struct PoslistCallbackCtx {
  Fts5Buffer *pBuf;               /* Append to this buffer */
  Fts5Colset *pColset;            /* Restrict matches to this column */
  int eState;                     /* See above */
};

/*
** TODO: Make this more efficient!
*/
static int fts5IndexColsetTest(Fts5Colset *pColset, int iCol){
  int i;
  for(i=0; i<pColset->nCol; i++){
    if( pColset->aiCol[i]==iCol ) return 1;
  }
  return 0;
}

static void fts5PoslistFilterCallback(
  Fts5Index *p, 
  void *pContext, 
  const u8 *pChunk, int nChunk
){
  PoslistCallbackCtx *pCtx = (PoslistCallbackCtx*)pContext;
  assert_nc( nChunk>=0 );
  if( nChunk>0 ){
    /* Search through to find the first varint with value 1. This is the
    ** start of the next columns hits. */
    int i = 0;
    int iStart = 0;

    if( pCtx->eState==2 ){
      int iCol;
      fts5FastGetVarint32(pChunk, i, iCol);
      if( fts5IndexColsetTest(pCtx->pColset, iCol) ){
        pCtx->eState = 1;
        fts5BufferAppendVarint(&p->rc, pCtx->pBuf, 1);
      }else{
        pCtx->eState = 0;
      }
    }

    do {
      while( i<nChunk && pChunk[i]!=0x01 ){
        while( pChunk[i] & 0x80 ) i++;
        i++;
      }
      if( pCtx->eState ){
        fts5BufferAppendBlob(&p->rc, pCtx->pBuf, i-iStart, &pChunk[iStart]);
      }
      if( i<nChunk ){
        int iCol;
        iStart = i;
        i++;
        if( i>=nChunk ){
          pCtx->eState = 2;
        }else{
          fts5FastGetVarint32(pChunk, i, iCol);
          pCtx->eState = fts5IndexColsetTest(pCtx->pColset, iCol);
          if( pCtx->eState ){
            fts5BufferAppendBlob(&p->rc, pCtx->pBuf, i-iStart, &pChunk[iStart]);
            iStart = i;
          }
        }
      }
    }while( i<nChunk );
  }
}

/*
** Iterator pIter currently points to a valid entry (not EOF). This
** function appends the position list data for the current entry to
** buffer pBuf. It does not make a copy of the position-list size
** field.
*/
static void fts5SegiterPoslist(
  Fts5Index *p,
  Fts5SegIter *pSeg,
  Fts5Colset *pColset,
  Fts5Buffer *pBuf
){
  if( pColset==0 ){
    fts5ChunkIterate(p, pSeg, (void*)pBuf, fts5PoslistCallback);
  }else{
    PoslistCallbackCtx sCtx;
    sCtx.pBuf = pBuf;
    sCtx.pColset = pColset;
    sCtx.eState = pColset ? fts5IndexColsetTest(pColset, 0) : 1;
    assert( sCtx.eState==0 || sCtx.eState==1 );
    fts5ChunkIterate(p, pSeg, (void*)&sCtx, fts5PoslistFilterCallback);
  }
}

/*
** Iterator pMulti currently points to a valid entry (not EOF). This
** function appends a copy of the position-list of the entry pMulti 
** currently points to to buffer pBuf.
**
** If an error occurs, an error code is left in p->rc. It is assumed
** no error has already occurred when this function is called.
*/
static int fts5MultiIterPoslist(
  Fts5Index *p,
  Fts5IndexIter *pMulti,
  Fts5Colset *pColset,
  Fts5Buffer *pBuf
){
  if( p->rc==SQLITE_OK ){
    int iSz;
    int iData;

    Fts5SegIter *pSeg = &pMulti->aSeg[ pMulti->aFirst[1].iFirst ];
    assert( fts5MultiIterEof(p, pMulti)==0 );


    /* WRITEPOSLISTSIZE */
    iSz = pBuf->n;
    fts5BufferSafeAppendVarint(pBuf, pSeg->nPos*2);
    iData = pBuf->n;

    fts5SegiterPoslist(p, pSeg, pColset, pBuf);

    if( pColset ){
      int nActual = pBuf->n - iData;
      if( nActual!=pSeg->nPos ){
        /* WRITEPOSLISTSIZE */
        if( nActual==0 ){
          return 1;
        }else{
          int nReq = sqlite3Fts5GetVarintLen((u32)(nActual*2));
          while( iSz<(iData-nReq) ){ pBuf->p[iSz++] = 0x80; }
          sqlite3Fts5PutVarint(&pBuf->p[iSz], nActual*2);
        }
      }
    }
  }

  return 0;
}

static void fts5DoclistIterNext(Fts5DoclistIter *pIter){
  u8 *p = pIter->aPoslist + pIter->nSize + pIter->nPoslist;

  assert( pIter->aPoslist );
  if( p>=pIter->aEof ){
    pIter->aPoslist = 0;
  }else{
    i64 iDelta;

    p += fts5GetVarint(p, (u64*)&iDelta);
    pIter->iRowid += iDelta;



    /* Read position list size */
    if( p[0] & 0x80 ){
      int nPos;

      pIter->nSize = fts5GetVarint32(p, nPos);
      pIter->nPoslist = (nPos>>1);
    }else{
      pIter->nPoslist = ((int)(p[0])) >> 1;
      pIter->nSize = 1;
    }

    pIter->aPoslist = p;
  }
}

static void fts5DoclistIterInit(
  Fts5Buffer *pBuf, 
  Fts5DoclistIter *pIter
){
  memset(pIter, 0, sizeof(*pIter));
  pIter->aPoslist = pBuf->p;
  pIter->aEof = &pBuf->p[pBuf->n];
  fts5DoclistIterNext(pIter);
}

#if 0
/*
** Append a doclist to buffer pBuf.
**
** This function assumes that space within the buffer has already been
** allocated.
*/
static void fts5MergeAppendDocid(

  Fts5Buffer *pBuf,               /* Buffer to write to */
  i64 *piLastRowid,               /* IN/OUT: Previous rowid written (if any) */
  i64 iRowid                      /* Rowid to append */
){
  assert( pBuf->n!=0 || (*piLastRowid)==0 );
  fts5BufferSafeAppendVarint(pBuf, iRowid - *piLastRowid);

  *piLastRowid = iRowid;
}
#endif

#define fts5MergeAppendDocid(pBuf, iLastRowid, iRowid) {       \
  assert( (pBuf)->n!=0 || (iLastRowid)==0 );                   \
  fts5BufferSafeAppendVarint((pBuf), (iRowid) - (iLastRowid)); \
  (iLastRowid) = (iRowid);                                     \
}

/*
** Buffers p1 and p2 contain doclists. This function merges the content
** of the two doclists together and sets buffer p1 to the result before
** returning.
**
** If an error occurs, an error code is left in p->rc. If an error has

    Fts5DoclistIter i1;
    Fts5DoclistIter i2;
    Fts5Buffer out;
    Fts5Buffer tmp;
    memset(&out, 0, sizeof(out));
    memset(&tmp, 0, sizeof(tmp));

    sqlite3Fts5BufferGrow(&p->rc, &out, p1->n + p2->n);
    fts5DoclistIterInit(p1, &i1);
    fts5DoclistIterInit(p2, &i2);
    while( p->rc==SQLITE_OK && (i1.aPoslist!=0 || i2.aPoslist!=0) ){
      if( i2.aPoslist==0 || (i1.aPoslist && i1.iRowid<i2.iRowid) ){
        /* Copy entry from i1 */
        fts5MergeAppendDocid(&out, iLastRowid, i1.iRowid);


        fts5BufferSafeAppendBlob(&out, i1.aPoslist, i1.nPoslist+i1.nSize);
        fts5DoclistIterNext(&i1);
      }
      else if( i1.aPoslist==0 || i2.iRowid!=i1.iRowid ){
        /* Copy entry from i2 */
        fts5MergeAppendDocid(&out, iLastRowid, i2.iRowid);


        fts5BufferSafeAppendBlob(&out, i2.aPoslist, i2.nPoslist+i2.nSize);
        fts5DoclistIterNext(&i2);
      }
      else{
        i64 iPos1 = 0;
        i64 iPos2 = 0;
        int iOff1 = 0;
        int iOff2 = 0;
        u8 *a1 = &i1.aPoslist[i1.nSize];
        u8 *a2 = &i2.aPoslist[i2.nSize];

        Fts5PoslistWriter writer;
        memset(&writer, 0, sizeof(writer));

        /* Merge the two position lists. */ 
        fts5MergeAppendDocid(&out, iLastRowid, i2.iRowid);
        fts5BufferZero(&tmp);

        sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1, &iPos1);
        sqlite3Fts5PoslistNext64(a2, i2.nPoslist, &iOff2, &iPos2);

        while( p->rc==SQLITE_OK && (iPos1>=0 || iPos2>=0) ){
          i64 iNew;
          if( iPos2<0 || (iPos1>=0 && iPos1<iPos2) ){
            iNew = iPos1;
            sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1, &iPos1);
          }else{
            iNew = iPos2;
            sqlite3Fts5PoslistNext64(a2, i2.nPoslist, &iOff2, &iPos2);
            if( iPos1==iPos2 ){
              sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1,&iPos1);
            }
          }
          p->rc = sqlite3Fts5PoslistWriterAppend(&tmp, &writer, iNew);
        }

        /* WRITEPOSLISTSIZE */
        fts5BufferSafeAppendVarint(&out, tmp.n * 2);
        fts5BufferSafeAppendBlob(&out, tmp.p, tmp.n);
        fts5DoclistIterNext(&i1);
        fts5DoclistIterNext(&i2);
      }
    }

    fts5BufferSet(&p->rc, p1, out.n, out.p);
    fts5BufferFree(&tmp);

}

static void fts5SetupPrefixIter(
  Fts5Index *p,                   /* Index to read from */
  int bDesc,                      /* True for "ORDER BY rowid DESC" */
  const u8 *pToken,               /* Buffer containing prefix to match */
  int nToken,                     /* Size of buffer pToken in bytes */
  Fts5Colset *pColset,            /* Restrict matches to these columns */
  Fts5IndexIter **ppIter          /* OUT: New iterator */
){
  Fts5Structure *pStruct;
  Fts5Buffer *aBuf;
  const int nBuf = 32;

  aBuf = (Fts5Buffer*)fts5IdxMalloc(p, sizeof(Fts5Buffer)*nBuf);
  pStruct = fts5StructureRead(p);

            fts5BufferSwap(&doclist, &aBuf[i]);
            fts5BufferZero(&doclist);
          }else{
            fts5MergePrefixLists(p, &doclist, &aBuf[i]);
            fts5BufferZero(&aBuf[i]);
          }
        }
        iLastRowid = 0;
      }

      if( 0==sqlite3Fts5BufferGrow(&p->rc, &doclist, 9) ){
        int iSave = doclist.n;
        assert( doclist.n!=0 || iLastRowid==0 );
        fts5BufferSafeAppendVarint(&doclist, iRowid - iLastRowid);
        if( fts5MultiIterPoslist(p, p1, pColset, &doclist) ){
          doclist.n = iSave;
        }else{
          iLastRowid = iRowid;
        }
      }
    }

    for(i=0; i<nBuf; i++){
      if( p->rc==SQLITE_OK ){
        fts5MergePrefixLists(p, &doclist, &aBuf[i]);
      }
      fts5BufferFree(&aBuf[i]);
    }
    fts5MultiIterFree(p, p1);

    pData = fts5IdxMalloc(p, sizeof(Fts5Data) + doclist.n);
    if( pData ){
      pData->p = (u8*)&pData[1];

}


/*
** Indicate that all subsequent calls to sqlite3Fts5IndexWrite() pertain
** to the document with rowid iRowid.
*/
int sqlite3Fts5IndexBeginWrite(Fts5Index *p, int bDelete, i64 iRowid){
  assert( p->rc==SQLITE_OK );

  /* Allocate the hash table if it has not already been allocated */
  if( p->pHash==0 ){
    p->rc = sqlite3Fts5HashNew(&p->pHash, &p->nPendingData);
  }

  /* Flush the hash table to disk if required */
  if( iRowid<p->iWriteRowid 
   || (iRowid==p->iWriteRowid && p->bDelete==0)
   || (p->nPendingData > p->nMaxPendingData) 
  ){
    fts5IndexFlush(p);
  }

  p->iWriteRowid = iRowid;
  p->bDelete = bDelete;
  return fts5IndexReturn(p);
}

/*
** Commit data to disk.
*/
int sqlite3Fts5IndexSync(Fts5Index *p, int bCommit){

    assert( p->pReader==0 );
    sqlite3_finalize(p->pWriter);
    sqlite3_finalize(p->pDeleter);
    sqlite3_finalize(p->pIdxWriter);
    sqlite3_finalize(p->pIdxDeleter);
    sqlite3_finalize(p->pIdxSelect);
    sqlite3Fts5HashFree(p->pHash);

    sqlite3_free(p->zDataTbl);
    sqlite3_free(p);
  }
  return rc;
}

/*

  const char *pToken, int nToken  /* Token to add or remove to or from index */
){
  int i;                          /* Used to iterate through indexes */
  int rc = SQLITE_OK;             /* Return code */
  Fts5Config *pConfig = p->pConfig;

  assert( p->rc==SQLITE_OK );
  assert( (iCol<0)==p->bDelete );

  /* Add the entry to the main terms index. */
  rc = sqlite3Fts5HashWrite(
      p->pHash, p->iWriteRowid, iCol, iPos, FTS5_MAIN_PREFIX, pToken, nToken
  );

  for(i=0; i<pConfig->nPrefix && rc==SQLITE_OK; i++){

** Open a new iterator to iterate though all rowid that match the 
** specified token or token prefix.
*/
int sqlite3Fts5IndexQuery(
  Fts5Index *p,                   /* FTS index to query */
  const char *pToken, int nToken, /* Token (or prefix) to query for */
  int flags,                      /* Mask of FTS5INDEX_QUERY_X flags */
  Fts5Colset *pColset,            /* Match these columns only */
  Fts5IndexIter **ppIter          /* OUT: New iterator object */
){
  Fts5Config *pConfig = p->pConfig;
  Fts5IndexIter *pRet = 0;
  int iIdx = 0;
  Fts5Buffer buf = {0, 0, 0};

      if( pStruct ){
        fts5MultiIterNew(p, pStruct, 1, flags, buf.p, nToken+1, -1, 0, &pRet);
        fts5StructureRelease(pStruct);
      }
    }else{
      int bDesc = (flags & FTS5INDEX_QUERY_DESC)!=0;
      buf.p[0] = FTS5_MAIN_PREFIX;
      fts5SetupPrefixIter(p, bDesc, buf.p, nToken+1, pColset, &pRet);
    }

    if( p->rc ){
      sqlite3Fts5IterClose(pRet);
      pRet = 0;
      fts5CloseReader(p);
    }

  assert( pIter->pIndex->rc==SQLITE_OK );
  *piRowid = pSeg->iRowid;
  *pn = pSeg->nPos;
  if( pSeg->iLeafOffset+pSeg->nPos <= pSeg->pLeaf->szLeaf ){
    *pp = &pSeg->pLeaf->p[pSeg->iLeafOffset];
  }else{
    fts5BufferZero(&pIter->poslist);
    fts5SegiterPoslist(pIter->pIndex, pSeg, 0, &pIter->poslist);
    *pp = pIter->poslist.p;
  }
  return fts5IndexReturn(pIter->pIndex);
}

/*
** This function is similar to sqlite3Fts5IterPoslist(), except that it
** copies the position list into the buffer supplied as the second 
** argument.
*/
int sqlite3Fts5IterPoslistBuffer(Fts5IndexIter *pIter, Fts5Buffer *pBuf){
  Fts5Index *p = pIter->pIndex;
  Fts5SegIter *pSeg = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
  assert( p->rc==SQLITE_OK );
  fts5BufferZero(pBuf);
  fts5SegiterPoslist(p, pSeg, 0, pBuf);
  return fts5IndexReturn(p);
}

/*
** Close an iterator opened by an earlier call to sqlite3Fts5IndexQuery().
*/
void sqlite3Fts5IterClose(Fts5IndexIter *pIter){

  const char *z,                  /* Index key to query for */
  int n,                          /* Size of index key in bytes */
  int flags,                      /* Flags for Fts5IndexQuery */
  u64 *pCksum                     /* IN/OUT: Checksum value */
){
  u64 cksum = *pCksum;
  Fts5IndexIter *pIdxIter = 0;
  int rc = sqlite3Fts5IndexQuery(p, z, n, flags, 0, &pIdxIter);

  while( rc==SQLITE_OK && 0==sqlite3Fts5IterEof(pIdxIter) ){
    i64 dummy;
    const u8 *pPos;
    int nPos;
    i64 rowid = sqlite3Fts5IterRowid(pIdxIter);
    rc = sqlite3Fts5IterPoslist(pIdxIter, &pPos, &nPos, &dummy);

    i64 iRowid = fts5MultiIterRowid(pIter);
    char *z = (char*)fts5MultiIterTerm(pIter, &n);

    /* If this is a new term, query for it. Update cksum3 with the results. */
    fts5TestTerm(p, &term, z, n, cksum2, &cksum3);

    poslist.n = 0;
    fts5SegiterPoslist(p, &pIter->aSeg[pIter->aFirst[1].iFirst] , 0, &poslist);
    while( 0==sqlite3Fts5PoslistNext64(poslist.p, poslist.n, &iOff, &iPos) ){
      int iCol = FTS5_POS2COLUMN(iPos);
      int iTokOff = FTS5_POS2OFFSET(iPos);
      cksum2 ^= fts5IndexEntryCksum(iRowid, iCol, iTokOff, -1, z, n);
    }
  }
  fts5TestTerm(p, &term, 0, 0, cksum2, &cksum3);

    *pRc = rc;
    return;
  }

  fts5DebugStructure(pRc, pBuf, p);
  fts5StructureRelease(p);
}

/*
** This is part of the fts5_decode() debugging aid.
**
** Arguments pBlob/nBlob contain an "averages" record. This function 
** appends a human-readable representation of record to the buffer passed 
** as the second argument. 
*/
static void fts5DecodeAverages(
  int *pRc,                       /* IN/OUT: error code */
  Fts5Buffer *pBuf,
  const u8 *pBlob, int nBlob
){
  int i = 0;
  const char *zSpace = "";

  while( i<nBlob ){
    u64 iVal;
    i += sqlite3Fts5GetVarint(&pBlob[i], &iVal);
    sqlite3Fts5BufferAppendPrintf(pRc, pBuf, "%s%d", zSpace, (int)iVal);
    zSpace = " ";
  }
}

/*
** Buffer (a/n) is assumed to contain a list of serialized varints. Read
** each varint and append its string representation to buffer pBuf. Return
** after either the input buffer is exhausted or a 0 value is read.
**
** The return value is the number of bytes read from the input buffer.

    for(fts5DlidxLvlNext(&lvl); lvl.bEof==0; fts5DlidxLvlNext(&lvl)){
      sqlite3Fts5BufferAppendPrintf(&rc, &s, 
          " %d(%lld)", lvl.iLeafPgno, lvl.iRowid
      );
    }
  }else if( iSegid==0 ){
    if( iRowid==FTS5_AVERAGES_ROWID ){
      fts5DecodeAverages(&rc, &s, a, n);
    }else{
      fts5DecodeStructure(&rc, &s, a, n);
    }
  }else{
    Fts5Buffer term;              /* Current term read from page */
    int szLeaf;                   /* Offset of pgidx in a[] */
    int iPgidxOff;

*/
#define FTS5_PLAN_MATCH          1       /* (<tbl> MATCH ?) */
#define FTS5_PLAN_SOURCE         2       /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL        3       /* An internal query */
#define FTS5_PLAN_SORTED_MATCH   4       /* (<tbl> MATCH ? ORDER BY rank) */
#define FTS5_PLAN_SCAN           5       /* No usable constraint */
#define FTS5_PLAN_ROWID          6       /* (rowid = ?) */

/*
** Set the SQLITE_INDEX_SCAN_UNIQUE flag in pIdxInfo->flags. Unless this
** extension is currently being used by a version of SQLite too old to
** support index-info flags. In that case this function is a no-op.
*/
static void fts5SetUniqueFlag(sqlite3_index_info *pIdxInfo){
#if SQLITE_VERSION_NUMBER>=3008012
  if( sqlite3_libversion_number()>=3008012 ){
    pIdxInfo->idxFlags |= SQLITE_INDEX_SCAN_UNIQUE;
  }
#endif
}

/*
** Implementation of the xBestIndex method for FTS5 tables. Within the 
** WHERE constraint, it searches for the following:
**
**   1. A MATCH constraint against the special column.
**   2. A MATCH constraint against the "rank" column.

  struct Constraint {
    int op;                       /* Mask against sqlite3_index_constraint.op */
    int fts5op;                   /* FTS5 mask for idxFlags */
    int iCol;                     /* 0==rowid, 1==tbl, 2==rank */
    int omit;                     /* True to omit this if found */
    int iConsIndex;               /* Index in pInfo->aConstraint[] */
  } aConstraint[] = {
    {SQLITE_INDEX_CONSTRAINT_MATCH|SQLITE_INDEX_CONSTRAINT_EQ, 
                                    FTS5_BI_MATCH,    1, 1, -1},
    {SQLITE_INDEX_CONSTRAINT_MATCH|SQLITE_INDEX_CONSTRAINT_EQ, 
                                    FTS5_BI_RANK,     2, 1, -1},
    {SQLITE_INDEX_CONSTRAINT_EQ,    FTS5_BI_ROWID_EQ, 0, 0, -1},
    {SQLITE_INDEX_CONSTRAINT_LT|SQLITE_INDEX_CONSTRAINT_LE, 
                                    FTS5_BI_ROWID_LE, 0, 0, -1},
    {SQLITE_INDEX_CONSTRAINT_GT|SQLITE_INDEX_CONSTRAINT_GE, 
                                    FTS5_BI_ROWID_GE, 0, 0, -1},
  };

    }
  }

  /* Calculate the estimated cost based on the flags set in idxFlags. */
  bHasMatch = BitFlagTest(idxFlags, FTS5_BI_MATCH);
  if( BitFlagTest(idxFlags, FTS5_BI_ROWID_EQ) ){
    pInfo->estimatedCost = bHasMatch ? 100.0 : 10.0;
    if( bHasMatch==0 ) fts5SetUniqueFlag(pInfo);
  }else if( BitFlagAllTest(idxFlags, FTS5_BI_ROWID_LE|FTS5_BI_ROWID_GE) ){
    pInfo->estimatedCost = bHasMatch ? 500.0 : 250000.0;
  }else if( BitFlagTest(idxFlags, FTS5_BI_ROWID_LE|FTS5_BI_ROWID_GE) ){
    pInfo->estimatedCost = bHasMatch ? 750.0 : 750000.0;
  }else{
    pInfo->estimatedCost = bHasMatch ? 1000.0 : 1000000.0;
  }

**
** The commands implemented by this function are documented in the "Special
** INSERT Directives" section of the documentation. It should be updated if
** more commands are added to this function.
*/
static int fts5SpecialInsert(
  Fts5Table *pTab,                /* Fts5 table object */
  const char *zCmd,               /* Text inserted into table-name column */
  sqlite3_value *pVal             /* Value inserted into rank column */
){
  Fts5Config *pConfig = pTab->pConfig;

  int rc = SQLITE_OK;
  int bError = 0;

  if( 0==sqlite3_stricmp("delete-all", zCmd) ){
    if( pConfig->eContent==FTS5_CONTENT_NORMAL ){
      fts5SetVtabError(pTab, 
          "'delete-all' may only be used with a "
          "contentless or external content fts5 table"
      );
      rc = SQLITE_ERROR;
    }else{
      rc = sqlite3Fts5StorageDeleteAll(pTab->pStorage);
    }
  }else if( 0==sqlite3_stricmp("rebuild", zCmd) ){
    if( pConfig->eContent==FTS5_CONTENT_NONE ){
      fts5SetVtabError(pTab, 
          "'rebuild' may not be used with a contentless fts5 table"
      );
      rc = SQLITE_ERROR;
    }else{
      rc = sqlite3Fts5StorageRebuild(pTab->pStorage);
    }
  }else if( 0==sqlite3_stricmp("optimize", zCmd) ){
    rc = sqlite3Fts5StorageOptimize(pTab->pStorage);
  }else if( 0==sqlite3_stricmp("merge", zCmd) ){
    int nMerge = sqlite3_value_int(pVal);
    rc = sqlite3Fts5StorageMerge(pTab->pStorage, nMerge);
  }else if( 0==sqlite3_stricmp("integrity-check", zCmd) ){
    rc = sqlite3Fts5StorageIntegrity(pTab->pStorage);
#ifdef SQLITE_DEBUG
  }else if( 0==sqlite3_stricmp("prefix-index", zCmd) ){
    pConfig->bPrefixIndex = sqlite3_value_int(pVal);
#endif
  }else{
    rc = sqlite3Fts5IndexLoadConfig(pTab->pIndex);
    if( rc==SQLITE_OK ){
      rc = sqlite3Fts5ConfigSetValue(pTab->pConfig, zCmd, pVal, &bError);
    }
    if( rc==SQLITE_OK ){
      if( bError ){
        rc = SQLITE_ERROR;
      }else{
        rc = sqlite3Fts5StorageConfigValue(pTab->pStorage, zCmd, pVal, 0);
      }
    }
  }
  return rc;
}

static int fts5SpecialDelete(
  Fts5Table *pTab, 
  sqlite3_value **apVal, 
  sqlite3_int64 *piRowid
){
  int rc = SQLITE_OK;
  int eType1 = sqlite3_value_type(apVal[1]);
  if( eType1==SQLITE_INTEGER ){
    sqlite3_int64 iDel = sqlite3_value_int64(apVal[1]);
    rc = sqlite3Fts5StorageSpecialDelete(pTab->pStorage, iDel, &apVal[2]);
  }
  return rc;
}

static void fts5StorageInsert(
  int *pRc, 
  Fts5Table *pTab, 
  sqlite3_value **apVal, 
  i64 *piRowid
){
  int rc = *pRc;
  if( rc==SQLITE_OK ){
    rc = sqlite3Fts5StorageContentInsert(pTab->pStorage, apVal, piRowid);
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3Fts5StorageIndexInsert(pTab->pStorage, apVal, *piRowid);
  }
  *pRc = rc;
}

/* 
** This function is the implementation of the xUpdate callback used by 
** FTS3 virtual tables. It is invoked by SQLite each time a row is to be
** inserted, updated or deleted.
**
** A delete specifies a single argument - the rowid of the row to remove.
** 
** Update and insert operations pass:
**
**   1. The "old" rowid, or NULL.
**   2. The "new" rowid.
**   3. Values for each of the nCol matchable columns.
**   4. Values for the two hidden columns (<tablename> and "rank").
*/
static int fts5UpdateMethod(
  sqlite3_vtab *pVtab,            /* Virtual table handle */
  int nArg,                       /* Size of argument array */
  sqlite3_value **apVal,          /* Array of arguments */
  sqlite_int64 *pRowid            /* OUT: The affected (or effected) rowid */
){
  Fts5Table *pTab = (Fts5Table*)pVtab;
  Fts5Config *pConfig = pTab->pConfig;
  int eType0;                     /* value_type() of apVal[0] */

  int rc = SQLITE_OK;             /* Return code */

  /* A transaction must be open when this is called. */
  assert( pTab->ts.eState==1 );

  assert( pVtab->zErrMsg==0 );
  assert( nArg==1 || nArg==(2+pConfig->nCol+2) );
  assert( nArg==1 
      || sqlite3_value_type(apVal[1])==SQLITE_INTEGER 
      || sqlite3_value_type(apVal[1])==SQLITE_NULL 
  );
  assert( pTab->pConfig->pzErrmsg==0 );
  pTab->pConfig->pzErrmsg = &pTab->base.zErrMsg;

  /* Put any active cursors into REQUIRE_SEEK state. */
  fts5TripCursors(pTab);

  eType0 = sqlite3_value_type(apVal[0]);
  if( eType0==SQLITE_NULL 
   && sqlite3_value_type(apVal[2+pConfig->nCol])!=SQLITE_NULL 
  ){
    /* A "special" INSERT op. These are handled separately. */
    const char *z = (const char*)sqlite3_value_text(apVal[2+pConfig->nCol]);
    if( pConfig->eContent!=FTS5_CONTENT_NORMAL 
      && 0==sqlite3_stricmp("delete", z) 
    ){
      rc = fts5SpecialDelete(pTab, apVal, pRowid);
    }else{
      rc = fts5SpecialInsert(pTab, z, apVal[2 + pConfig->nCol + 1]);
    }
  }else{
    /* A regular INSERT, UPDATE or DELETE statement. The trick here is that
    ** any conflict on the rowid value must be detected before any 
    ** modifications are made to the database file. There are 4 cases:
    **
    **   1) DELETE
    **   2) UPDATE (rowid not modified)
    **   3) UPDATE (rowid modified)
    **   4) INSERT
    **
    ** Cases 3 and 4 may violate the rowid constraint.
    */


    int eConflict = sqlite3_vtab_on_conflict(pConfig->db);

    assert( eType0==SQLITE_INTEGER || eType0==SQLITE_NULL );

    assert( nArg!=1 || eType0==SQLITE_INTEGER );


    /* Filter out attempts to run UPDATE or DELETE on contentless tables.
    ** This is not suported.  */
    if( eType0==SQLITE_INTEGER && fts5IsContentless(pTab) ){

      pTab->base.zErrMsg = sqlite3_mprintf(
          "cannot %s contentless fts5 table: %s", 
          (nArg>1 ? "UPDATE" : "DELETE from"), pConfig->zName
      );
      rc = SQLITE_ERROR;
    }

    /* Case 1: DELETE */
    else if( nArg==1 ){
      i64 iDel = sqlite3_value_int64(apVal[0]);  /* Rowid to delete */
      rc = sqlite3Fts5StorageDelete(pTab->pStorage, iDel);
    }

    /* Case 2: INSERT */
    else if( eType0!=SQLITE_INTEGER ){     
      /* If this is a REPLACE, first remove the current entry (if any) */
      if( eConflict==SQLITE_REPLACE 
       && sqlite3_value_type(apVal[1])==SQLITE_INTEGER 


      ){
        i64 iNew = sqlite3_value_int64(apVal[1]);  /* Rowid to delete */
        rc = sqlite3Fts5StorageDelete(pTab->pStorage, iNew);


      }

      fts5StorageInsert(&rc, pTab, apVal, pRowid);
    }

    /* Case 2: UPDATE */
    else{
      i64 iOld = sqlite3_value_int64(apVal[0]);  /* Old rowid */
      i64 iNew = sqlite3_value_int64(apVal[1]);  /* New rowid */
      if( iOld!=iNew ){
        if( eConflict==SQLITE_REPLACE ){
          rc = sqlite3Fts5StorageDelete(pTab->pStorage, iOld);
          if( rc==SQLITE_OK ){
            rc = sqlite3Fts5StorageDelete(pTab->pStorage, iNew);
          }
          fts5StorageInsert(&rc, pTab, apVal, pRowid);
        }else{
          rc = sqlite3Fts5StorageContentInsert(pTab->pStorage, apVal, pRowid);
          if( rc==SQLITE_OK ){
            rc = sqlite3Fts5StorageDelete(pTab->pStorage, iOld);
          }
          if( rc==SQLITE_OK ){
            rc = sqlite3Fts5StorageIndexInsert(pTab->pStorage, apVal, *pRowid);
          }
        }
      }else{
        rc = sqlite3Fts5StorageDelete(pTab->pStorage, iOld);
        fts5StorageInsert(&rc, pTab, apVal, pRowid);
      }
    }
  }

  pTab->pConfig->pzErrmsg = 0;
  return rc;
}

/*
** Implementation of xSync() method. 
*/

    int rc2;
    sqlite3_bind_int64(pSeek, 1, iDel);
    if( sqlite3_step(pSeek)==SQLITE_ROW ){
      int iCol;
      Fts5InsertCtx ctx;
      ctx.pStorage = p;
      ctx.iCol = -1;
      rc = sqlite3Fts5IndexBeginWrite(p->pIndex, 1, iDel);
      for(iCol=1; rc==SQLITE_OK && iCol<=pConfig->nCol; iCol++){
        if( pConfig->abUnindexed[iCol-1] ) continue;
        ctx.szCol = 0;
        rc = sqlite3Fts5Tokenize(pConfig, 
            FTS5_TOKENIZE_DOCUMENT,
            (const char*)sqlite3_column_text(pSeek, iCol),
            sqlite3_column_bytes(pSeek, iCol),

  /* Delete the index records */
  if( rc==SQLITE_OK ){
    int iCol;
    Fts5InsertCtx ctx;
    ctx.pStorage = p;
    ctx.iCol = -1;

    rc = sqlite3Fts5IndexBeginWrite(p->pIndex, 1, iDel);
    for(iCol=0; rc==SQLITE_OK && iCol<pConfig->nCol; iCol++){
      if( pConfig->abUnindexed[iCol] ) continue;
      ctx.szCol = 0;
      rc = sqlite3Fts5Tokenize(pConfig, 
        FTS5_TOKENIZE_DOCUMENT,
        (const char*)sqlite3_value_text(apVal[iCol]),
        sqlite3_value_bytes(apVal[iCol]),

    rc = fts5StorageGetStmt(p, FTS5_STMT_SCAN, &pScan, 0);
  }

  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pScan) ){
    i64 iRowid = sqlite3_column_int64(pScan, 0);

    sqlite3Fts5BufferZero(&buf);
    rc = sqlite3Fts5IndexBeginWrite(p->pIndex, 0, iRowid);
    for(ctx.iCol=0; rc==SQLITE_OK && ctx.iCol<pConfig->nCol; ctx.iCol++){
      ctx.szCol = 0;
      if( pConfig->abUnindexed[ctx.iCol]==0 ){
        rc = sqlite3Fts5Tokenize(pConfig, 
            FTS5_TOKENIZE_DOCUMENT,
            (const char*)sqlite3_column_text(pScan, ctx.iCol+1),
            sqlite3_column_bytes(pScan, ctx.iCol+1),

      *piRowid = sqlite3_last_insert_rowid(p->pConfig->db);
    }
  }
  return rc;
}

/*
** Insert a new row into the FTS content table.
*/
int sqlite3Fts5StorageContentInsert(
  Fts5Storage *p, 
  sqlite3_value **apVal, 
  i64 *piRowid
){
  Fts5Config *pConfig = p->pConfig;
  int rc = SQLITE_OK;

  /* Insert the new row into the %_content table. */
  if( pConfig->eContent!=FTS5_CONTENT_NORMAL ){
    if( sqlite3_value_type(apVal[1])==SQLITE_INTEGER ){
      *piRowid = sqlite3_value_int64(apVal[1]);
    }else{
      rc = fts5StorageNewRowid(p, piRowid);
    }
  }else{
    sqlite3_stmt *pInsert = 0;    /* Statement to write %_content table */
    int i;                        /* Counter variable */
#if 0
    if( eConflict==SQLITE_REPLACE ){
      eStmt = FTS5_STMT_REPLACE_CONTENT;
      rc = fts5StorageDeleteFromIndex(p, sqlite3_value_int64(apVal[1]));
    }else{
      eStmt = FTS5_STMT_INSERT_CONTENT;
    }
#endif
    if( rc==SQLITE_OK ){
      rc = fts5StorageGetStmt(p, FTS5_STMT_INSERT_CONTENT, &pInsert, 0);
    }
    for(i=1; rc==SQLITE_OK && i<=pConfig->nCol+1; i++){
      rc = sqlite3_bind_value(pInsert, i, apVal[i]);
    }
    if( rc==SQLITE_OK ){
      sqlite3_step(pInsert);
      rc = sqlite3_reset(pInsert);
    }
    *piRowid = sqlite3_last_insert_rowid(pConfig->db);
  }

  return rc;
}

/*
** Insert new entries into the FTS index and %_docsize table.
*/
int sqlite3Fts5StorageIndexInsert(
  Fts5Storage *p, 
  sqlite3_value **apVal, 
  i64 iRowid
){
  Fts5Config *pConfig = p->pConfig;
  int rc = SQLITE_OK;             /* Return code */



  Fts5InsertCtx ctx;              /* Tokenization callback context object */
  Fts5Buffer buf;                 /* Buffer used to build up %_docsize blob */

  memset(&buf, 0, sizeof(Fts5Buffer));
  ctx.pStorage = p;
  rc = fts5StorageLoadTotals(p, 1);


  if( rc==SQLITE_OK ){





























    rc = sqlite3Fts5IndexBeginWrite(p->pIndex, 0, iRowid);

  }
  for(ctx.iCol=0; rc==SQLITE_OK && ctx.iCol<pConfig->nCol; ctx.iCol++){
    ctx.szCol = 0;
    if( pConfig->abUnindexed[ctx.iCol]==0 ){
      rc = sqlite3Fts5Tokenize(pConfig, 
          FTS5_TOKENIZE_DOCUMENT,
          (const char*)sqlite3_value_text(apVal[ctx.iCol+2]),
          sqlite3_value_bytes(apVal[ctx.iCol+2]),
          (void*)&ctx,
          fts5StorageInsertCallback
      );
    }
    sqlite3Fts5BufferAppendVarint(&rc, &buf, ctx.szCol);
    p->aTotalSize[ctx.iCol] += (i64)ctx.szCol;
  }
  p->nTotalRow++;

  /* Write the %_docsize record */
  if( rc==SQLITE_OK ){
    rc = fts5StorageInsertDocsize(p, iRowid, &buf);
  }
  sqlite3_free(buf.p);

  /* Write the averages record */
  if( rc==SQLITE_OK ){
    rc = fts5StorageSaveTotals(p);
  }

  sqlite3_value **apVal           /* Arguments for the indexing scheme */
){
  Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
  int rc;
  const int flags = FTS5INDEX_QUERY_SCAN;

  fts5VocabResetCursor(pCsr);
  rc = sqlite3Fts5IndexQuery(pCsr->pIndex, 0, 0, flags, 0, &pCsr->pIter);
  if( rc==SQLITE_OK ){
    rc = fts5VocabNextMethod(pCursor);
  }

  return rc;
}

  A = sqlite3Fts5ParseNode(pParse, FTS5_STRING, 0, 0, X); 
}
cnearset(A) ::= colset(X) COLON nearset(Y). { 
  sqlite3Fts5ParseSetColset(pParse, Y, X);
  A = sqlite3Fts5ParseNode(pParse, FTS5_STRING, 0, 0, Y); 
}

%type colset {Fts5Colset*}
%destructor colset { sqlite3_free($$); }
%type colsetlist {Fts5Colset*}
%destructor colsetlist { sqlite3_free($$); }

colset(A) ::= LCP colsetlist(X) RCP. { A = X; }
colset(A) ::= STRING(X). {
  A = sqlite3Fts5ParseColset(pParse, 0, &X);
}

  INSERT INTO t3 VALUES('a one');
  INSERT INTO t3 VALUES('a two');
  INSERT INTO t3 VALUES('a three');
  INSERT INTO t3 VALUES('a four');
  INSERT INTO t3 VALUES('a five');
  INSERT INTO t3(t3, rank) VALUES('rank', 'bm25()');
}


do_execsql_test 4.3.2 {
  SELECT * FROM t3
  WHERE t3 MATCH 'a' AND rank MATCH 'rowidmod(4)' 
  ORDER BY rank ASC
} {
  {a four} {a one} {a five} {a two} {a three}
}

do_execsql_test 4.3.3 {
  SELECT *, rank FROM t3
  WHERE t3 MATCH 'a' AND rank MATCH 'rowidmod(3)' 
  ORDER BY rank ASC
} {
  {a three} 0 {a one} 1 {a four} 1 {a two} 2 {a five} 2 
}

do_execsql_test 4.3.4 {
  SELECT * FROM t3('a', 'rowidmod(4)') ORDER BY rank ASC;
} {
  {a four} {a one} {a five} {a two} {a three}
}

do_execsql_test 4.3.5 {
  SELECT *, rank FROM t3('a', 'rowidmod(3)') ORDER BY rank ASC
} {
  {a three} 0 {a one} 1 {a four} 1 {a two} 2 {a five} 2 
}

do_catchsql_test 4.4.3 {
  SELECT *, rank FROM t3 WHERE t3 MATCH 'a' AND rank MATCH 'xyz(3)' 
} {1 {no such function: xyz}}
do_catchsql_test 4.4.4 {
  SELECT *, rank FROM t3 WHERE t3 MATCH 'a' AND rank MATCH NULL
} {1 {parse error in rank function: }}

# 2015 Sep 27
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#

source [file join [file dirname [info script]] fts5_common.tcl]
set testprefix fts5onepass

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts5 {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE ft USING fts5(content);
  INSERT INTO ft(rowid, content) VALUES(1, '1 2 3');
  INSERT INTO ft(rowid, content) VALUES(2, '4 5 6');
  INSERT INTO ft(rowid, content) VALUES(3, '7 8 9');
}

#-------------------------------------------------------------------------
# Check that UPDATE and DELETE statements that feature "WHERE rowid=?" or 
# or "WHERE rowid=?" clauses do not use statement journals. But that other
# DELETE and UPDATE statements do.
#
# Note: "MATCH ? AND rowid=?" does use a statement journal.
#
foreach {tn sql uses} {
  1.1 { DELETE FROM ft } 1
  1.2 { DELETE FROM ft WHERE rowid=? } 0
  1.3 { DELETE FROM ft WHERE rowid=? } 0
  1.4 { DELETE FROM ft WHERE ft MATCH '1' } 1
  1.5 { DELETE FROM ft WHERE ft MATCH '1' AND rowid=? } 1
  1.6 { DELETE FROM ft WHERE ft MATCH '1' AND rowid=? } 1

  2.1 { UPDATE ft SET content='a b c' } 1
  2.2 { UPDATE ft SET content='a b c' WHERE rowid=? } 0
  2.3 { UPDATE ft SET content='a b c' WHERE rowid=? } 0
  2.4 { UPDATE ft SET content='a b c' WHERE ft MATCH '1' } 1
  2.5 { UPDATE ft SET content='a b c' WHERE ft MATCH '1' AND rowid=? } 1
  2.6 { UPDATE ft SET content='a b c' WHERE ft MATCH '1' AND rowid=? } 1
} {
  do_test 1.$tn { sql_uses_stmt db $sql } $uses
}

#-------------------------------------------------------------------------
# Check that putting a "DELETE/UPDATE ... WHERE rowid=?" statement in a
# trigger program does not prevent the VM from using a statement 
# transaction. Even if the calling statement cannot hit a constraint.
#
do_execsql_test 2.0 {
  CREATE TABLE t1(x);

  CREATE TRIGGER t1_ai AFTER INSERT ON t1 BEGIN
    DELETE FROM ft WHERE rowid=new.x;
  END;

  CREATE TRIGGER t1_ad AFTER DELETE ON t1 BEGIN
    UPDATE ft SET content = 'a b c' WHERE rowid=old.x;
  END;

  CREATE TRIGGER t1_bu BEFORE UPDATE ON t1 BEGIN
    DELETE FROM ft WHERE rowid=old.x;
  END;
}

foreach {tn sql uses} {
  1 { INSERT INTO t1 VALUES(1)      } 1
  2 { DELETE FROM t1 WHERE x=4      } 1
  3 { UPDATE t1 SET x=10 WHERE x=11 } 1
} {
  do_test 2.$tn { sql_uses_stmt db $sql } $uses
}

#-------------------------------------------------------------------------
# Test that an "UPDATE ... WHERE rowid=?" works and does not corrupt the
# index when it strikes a constraint. Both inside and outside a 
# transaction.
#
foreach {tn tcl1 tcl2}  {
  1 {} {}

  2 {
    execsql BEGIN
  } {
    if {[sqlite3_get_autocommit db]==1} { error "transaction rolled back!" }
    execsql COMMIT
  }
} {

  do_execsql_test 3.$tn.0 {
    DROP TABLE IF EXISTS ft2;
    CREATE VIRTUAL TABLE ft2 USING fts5(content);
    INSERT INTO ft2(rowid, content) VALUES(1, 'a b c');
    INSERT INTO ft2(rowid, content) VALUES(2, 'a b d');
    INSERT INTO ft2(rowid, content) VALUES(3, 'a b e');
  }

  eval $tcl1
  foreach {tn2 sql content} {
    1 { UPDATE ft2 SET rowid=2 WHERE rowid=1 }
      { 1 {a b c} 2 {a b d} 3 {a b e} }

    2 { 
      INSERT INTO ft2(rowid, content) VALUES(4, 'a b f');
      UPDATE ft2 SET rowid=5 WHERE rowid=4;
      UPDATE ft2 SET rowid=3 WHERE rowid=5;
    } { 1 {a b c} 2 {a b d} 3 {a b e} 5 {a b f} }

    3 {
      UPDATE ft2 SET rowid=3 WHERE rowid=4;           -- matches 0 rows
      UPDATE ft2 SET rowid=2 WHERE rowid=3;
    } { 1 {a b c} 2 {a b d} 3 {a b e} 5 {a b f} }

    4 {
      INSERT INTO ft2(rowid, content) VALUES(4, 'a b g');
      UPDATE ft2 SET rowid=-1 WHERE rowid=4;
      UPDATE ft2 SET rowid=3 WHERE rowid=-1;
    } {-1 {a b g} 1 {a b c} 2 {a b d} 3 {a b e} 5 {a b f} }

    5 {
      DELETE FROM ft2 WHERE rowid=451;
      DELETE FROM ft2 WHERE rowid=-1;
      UPDATE ft2 SET rowid = 2 WHERE rowid = 1;
    } {1 {a b c} 2 {a b d} 3 {a b e} 5 {a b f} }
  } {
    do_catchsql_test 3.$tn.$tn2.a $sql {1 {constraint failed}}
    do_execsql_test  3.$tn.$tn2.b { SELECT rowid, content FROM ft2 } $content

    do_execsql_test  3.$tn.$tn2.c { 
      INSERT INTO ft2(ft2) VALUES('integrity-check');
    }
  }
  eval $tcl2
}

#-------------------------------------------------------------------------
# Check that DELETE and UPDATE operations can be done without flushing
# the in-memory hash table to disk.
#
reset_db
do_execsql_test 4.1.1 {
  CREATE VIRTUAL TABLE ttt USING fts5(x);
  BEGIN;
    INSERT INTO ttt(rowid, x) VALUES(1, 'a b c');
    INSERT INTO ttt(rowid, x) VALUES(2, 'a b c');
    INSERT INTO ttt(rowid, x) VALUES(3, 'a b c');
  COMMIT
}
do_test 4.1.2 { fts5_level_segs ttt } {1}

do_execsql_test 4.2.1 {
  BEGIN;
    DELETE FROM ttt WHERE rowid=1;
    DELETE FROM ttt WHERE rowid=3;
    INSERT INTO ttt(rowid, x) VALUES(4, 'd e f');
    INSERT INTO ttt(rowid, x) VALUES(5, 'd e f');
  COMMIT;
} {}
do_test 4.2.2 { fts5_level_segs ttt } {2}


do_execsql_test 4.3.1 {
  BEGIN;
    UPDATE ttt SET x = 'd e f' WHERE rowid = 2;
    UPDATE ttt SET x = 'A B C' WHERE rowid = 4;
    INSERT INTO ttt(rowid, x) VALUES(6, 'd e f');
  COMMIT;
} {}
do_test 4.2.2 { fts5_level_segs ttt } {3}

finish_test

# 2014 Jan 08
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#
# Tests focused on phrase queries.
#

source [file join [file dirname [info script]] fts5_common.tcl]
set testprefix fts5phrase

# If SQLITE_ENABLE_FTS5 is defined, omit this file.
ifcapable !fts5 {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE t3 USING fts5(a, b, c);
  INSERT INTO t3 VALUES('d e a', 'd i j j f', 'i j i e b f h'); -- 1
  INSERT INTO t3 VALUES('g a e', 'f g i g a', 'h d g i g h c'); -- 2
  INSERT INTO t3 VALUES('e a d', 'e i h a f', 'c e h i f b i'); -- 3
  INSERT INTO t3 VALUES('a g c', 'd j d j c', 'c d f j i g j'); -- 4
  INSERT INTO t3 VALUES('b c b', 'j g c d f', 'j c j d g f b'); -- 5
  INSERT INTO t3 VALUES('j a d', 'e b i h h', 'c c f g d i d'); -- 6
  INSERT INTO t3 VALUES('a d f', 'h g i i i', 'e a g c i f b'); -- 7
  INSERT INTO t3 VALUES('g f d', 'f c g b j', 'b b h h h j j'); -- 8
  INSERT INTO t3 VALUES('f h g', 'c j f g j', 'd h d f e b h'); -- 9
  INSERT INTO t3 VALUES('f h d', 'c i a d b', 'g b j b a d e'); -- 10
  INSERT INTO t3 VALUES('j h h', 'j i h a g', 'd e i e a g j'); -- 11
  INSERT INTO t3 VALUES('a b e', 'h g a g c', 'h c a a d e g'); -- 12
  INSERT INTO t3 VALUES('a j g', 'i h i f i', 'a g h j g i b'); -- 13
  INSERT INTO t3 VALUES('j h e', 'f e d i e', 'i d c f e d c'); -- 14
  INSERT INTO t3 VALUES('d j d', 'd b i a c', 'g d h i d b e'); -- 15
  INSERT INTO t3 VALUES('h j e', 'e b b c f', 'j a f g h d j'); -- 16
  INSERT INTO t3 VALUES('c b j', 'c a b a i', 'h f i d a d c'); -- 17
  INSERT INTO t3 VALUES('e e d', 'i d f c c', 'g i d a f e a'); -- 18
  INSERT INTO t3 VALUES('e i g', 'e a b i h', 'i f d d a d f'); -- 19
  INSERT INTO t3 VALUES('h g f', 'b h h j d', 'i f d e g j a'); -- 20
  INSERT INTO t3 VALUES('e h f', 'j c b c f', 'j a j g h a c'); -- 21
  INSERT INTO t3 VALUES('d c h', 'b g i c e', 'i i c d e h i'); -- 22
  INSERT INTO t3 VALUES('a h i', 'a g d f f', 'e f i i b b h'); -- 23
  INSERT INTO t3 VALUES('d d g', 'c c b c g', 'g c h e b c e'); -- 24
  INSERT INTO t3 VALUES('a b b', 'b f a d i', 'd a h a b c i'); -- 25
  INSERT INTO t3 VALUES('a f d', 'a j e a h', 'j i h j a i f'); -- 26
  INSERT INTO t3 VALUES('d j d', 'h a d i a', 'h h f j h g a'); -- 27
  INSERT INTO t3 VALUES('g a e', 'd g f a g', 'i d b c g g j'); -- 28
  INSERT INTO t3 VALUES('j e h', 'g h j h g', 'd a e j a a h'); -- 29
  INSERT INTO t3 VALUES('e j e', 'g e j g c', 'f c e b e e a'); -- 30
  INSERT INTO t3 VALUES('h f f', 'i j g e c', 'j j f c a i j'); -- 31
  INSERT INTO t3 VALUES('a g c', 'c g d b i', 'g h c b a a f'); -- 32
  INSERT INTO t3 VALUES('c h i', 'j d h e e', 'a h i d c c j'); -- 33
  INSERT INTO t3 VALUES('d a c', 'e d d b j', 'c e b b h i h'); -- 34
  INSERT INTO t3 VALUES('d f h', 'c a f c c', 'j b b c c j f'); -- 35
  INSERT INTO t3 VALUES('b g h', 'g c c c f', 'c g c f h e e'); -- 36
  INSERT INTO t3 VALUES('f e a', 'b h f j h', 'j g h f d g f'); -- 37
  INSERT INTO t3 VALUES('h f a', 'a e i j g', 'f d a f d f c'); -- 38
  INSERT INTO t3 VALUES('f i c', 'f i i i i', 'e c f d h j f'); -- 39
  INSERT INTO t3 VALUES('h h d', 'd i e d i', 'd f e i a h a'); -- 40
  INSERT INTO t3 VALUES('f g c', 'd a f c h', 'b b g j c e g'); -- 41
  INSERT INTO t3 VALUES('h i h', 'h d j d e', 'e d b b i e g'); -- 42
  INSERT INTO t3 VALUES('b h i', 'j e i d a', 'j j h e e c a'); -- 43
  INSERT INTO t3 VALUES('g i g', 'f c c f d', 'a c i c a d a'); -- 44
  INSERT INTO t3 VALUES('c c f', 'a b j d b', 'c a e g f e c'); -- 45
  INSERT INTO t3 VALUES('d h j', 'g c b j d', 'e a h f h j g'); -- 46
  INSERT INTO t3 VALUES('a a d', 'j e j a i', 'i d c f f f b'); -- 47
  INSERT INTO t3 VALUES('b g j', 'e c i h f', 'd d h b g a d'); -- 48
  INSERT INTO t3 VALUES('c i a', 'a c c c c', 'e h i e h i e'); -- 49
  INSERT INTO t3 VALUES('f f c', 'f f b i i', 'f f a j e c i'); -- 50
}

proc pmatch {col expr} {
  return [expr {[string first $expr $col]>=0}]
}
db func pmatch pmatch

foreach {tn cols tokens} {
  1 a         "c c"
  2 b         "c c"
  3 c         "c c"
  4 {a b c}   "c c"
  5 {a b c}   "b h"
  6 {a b}     "b h"
  7 {a c}     "b h"
  8 {c a}     "b h"
  9 {c}       "i e"
  10 {b}      "i e"
  11 {a}      "i e"
} {
  set fts   "{$cols}:[join $tokens +]"
  set where [list]
  foreach c $cols { lappend where "pmatch($c, '$tokens')" }
  set where [join $where " OR "]

  set res [db eval "SELECT rowid FROM t3 WHERE $where"]
  do_execsql_test "1.$tn.$fts->([llength $res] rows)" { 
    SELECT rowid FROM t3($fts) 
  } $res
}

do_execsql_test 2.0 {
  SELECT rowid,
    highlight(t3, 0, '*', '*'),
    highlight(t3, 1, '*', '*'),
    highlight(t3, 2, '*', '*')
  FROM t3('a:f+f')
} {
  31 {h *f f*} {i j g e c} {j j f c a i j} 
  50 {*f f* c} {f f b i i} {f f a j e c i}
}

finish_test

foreach {tn q res} {
  1 "SELECT rowid FROM t1 WHERE t1 MATCH '\xCA\xCB*'" 1
  2 "SELECT rowid FROM t1 WHERE t1 MATCH '\u1234\u5678*'" 2
} {
  do_execsql_test 2.3.$tn $q $res
}

#-------------------------------------------------------------------------
# Check that prefix queries with:
#
#   * a column filter, and
#   * no prefix index.
#
# work Ok.
#
do_execsql_test 3.0 {
  CREATE VIRTUAL TABLE t3 USING fts5(a, b, c);
  INSERT INTO t3(t3, rank) VALUES('pgsz', 32);
  BEGIN;
    INSERT INTO t3 VALUES('acb ccc bba', 'cca bba bca', 'bbc ccc bca'); -- 1
    INSERT INTO t3 VALUES('cbb cac cab', 'abb aac bba', 'aab ccc cac'); -- 2
    INSERT INTO t3 VALUES('aac bcb aac', 'acb bcb caa', 'aca bab bca'); -- 3
    INSERT INTO t3 VALUES('aab ccb ccc', 'aca cba cca', 'aca aac cbb'); -- 4
    INSERT INTO t3 VALUES('bac aab bab', 'ccb bac cba', 'acb aba abb'); -- 5
    INSERT INTO t3 VALUES('bab abc ccb', 'acb cba abb', 'cbb aaa cab'); -- 6
    INSERT INTO t3 VALUES('cbb bbc baa', 'aab aca baa', 'bcc cca aca'); -- 7
    INSERT INTO t3 VALUES('abc bba abb', 'cac abc cba', 'acc aac cac'); -- 8
    INSERT INTO t3 VALUES('bbc bbc cab', 'bcb ccb cba', 'bcc cac acb'); -- 9
  COMMIT;
}

foreach {tn match res} {
  1 "a : c*" {1 2 4 6 7 9}
  2 "b : c*" {1 3 4 5 6 8 9}
  3 "c : c*" {1 2 4 6 7 8 9}
  4 "a : b*" {1 3 5 6 7 8 9}
  5 "b : b*" {1 2 3 5 7 9}
  6 "c : b*" {1 3 7 9}
  7 "a : a*" {1 3 4 5 6 8}
  8 "b : a*" {2 3 4 6 7 8}
  9 "c : a*" {2 3 4 5 6 7 8 9}
} {
  do_execsql_test 3.1.$tn {
    SELECT rowid FROM t3($match)
  } $res
}

do_test 3.2 {
  expr srand(0)
  execsql { DELETE FROM t3 }
  for {set i 0} {$i < 1000} {incr i} {
    set a [fts5_rnddoc 3]
    set b [fts5_rnddoc 8]
    set c [fts5_rnddoc 20]
    execsql { INSERT INTO t3 VALUES($a, $b, $c) }
  }
  execsql { INSERT INTO t3(t3) VALUES('integrity-check') }
} {}

proc gmatch {col pattern} {
  expr {[lsearch -glob $col $pattern]>=0}
}
db func gmatch gmatch

proc ghl {col pattern} {
  foreach t $col {
    if {[string match $pattern $t]} {
      lappend res "*$t*"
    } else {
      lappend res $t
    }
  }
  set res
}
db func ghl ghl

set COLS(a) 0
set COLS(b) 1
set COLS(c) 2

for {set x 0} {$x<2} {incr x} {
  foreach {tn pattern} {
    1  {xa*}
    2  {xb*}
    3  {xc*}
    4  {xd*}
    5  {xe*}
    6  {xf*}
    7  {xg*}
    8  {xh*}
    9  {xi*}
    10 {xj*}
  } {
    foreach col {a b c} {

      # Check that the list of returned rowids is correct.
      #
      set res [db eval "SELECT rowid FROM t3 WHERE gmatch($col, '$pattern')"]
      set query "$col : $pattern"
      do_execsql_test 3.3.$x.$tn.$col.rowid {
        SELECT rowid FROM t3($query);
      } $res

      # Check that the highlight() function works.
      #
      set res [db eval \
        "SELECT ghl($col, '$pattern') FROM t3 WHERE gmatch($col, '$pattern')"
      ]
      set idx $COLS($col)
      do_execsql_test 3.3.$x.$tn.$col.highlight {
        SELECT highlight(t3, $idx, '*', '*') FROM t3($query);
      } $res
    }

    foreach colset {{a b} {b c} {c a} {a c} {b a}} {
      # Check that the list of returned rowids is correct.
      #
      foreach {col1 col2} $colset {}
      set expr "gmatch($col1, '$pattern') OR gmatch($col2, '$pattern')"
      set res [db eval "SELECT rowid FROM t3 WHERE $expr"]
      set query "{$colset} : $pattern"
      do_execsql_test 3.3.$x.$tn.{$colset}.rowid {
        SELECT rowid FROM t3($query);
      } $res

      set resq    "SELECT ghl($col1, '$pattern'), ghl($col2, '$pattern')"
      append resq " FROM t3 WHERE $expr"
      set res [db eval $resq]
      set idx1 $COLS($col1)
      set idx2 $COLS($col2)
      do_execsql_test 3.3.$x.$tn.{$colset}.highlight {
        SELECT highlight(t3, $idx1, '*', '*'), highlight(t3, $idx2, '*', '*')
          FROM t3($query)
      } $res
    }
  }
  execsql { INSERT INTO t3(t3) VALUES('optimize') }
  execsql { INSERT INTO t3(t3) VALUES('integrity-check') }
}


finish_test

# If SQLITE_ENABLE_FTS5 is defined, omit this file.
ifcapable !fts5 {
  finish_test
  return
}


#-------------------------------------------------------------------------
#
set doc "x x [string repeat {y } 50]z z"
do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE t1 USING fts5(x);
  INSERT INTO t1(t1, rank) VALUES('pgsz', 32);
  BEGIN;

  COMMIT;
} {}

do_execsql_test 5.4 {
  SELECT rowid FROM tt WHERE tt MATCH 'a*';
} {1 2}



do_execsql_test 5.5 {
  DELETE FROM tt;
  BEGIN;
    INSERT INTO tt VALUES('aa');
    INSERT INTO tt VALUES('ab');
    INSERT INTO tt VALUES('aa');
    INSERT INTO tt VALUES('ab');

do_catchsql_test 6.2 { 
  SELECT * FROM xyz WHERE xyz MATCH '' 
} {1 {fts5: syntax error near ""}}
do_catchsql_test 6.3 { 
  SELECT * FROM xyz WHERE xyz MATCH NULL 
} {1 {fts5: syntax error near ""}}

#-------------------------------------------------------------------------

do_execsql_test 7.1 {
  CREATE VIRTUAL TABLE ft2 USING fts5(content);
  INSERT INTO ft2(rowid, content) VALUES(1, 'a b c');
  INSERT INTO ft2(rowid, content) VALUES(2, 'a b d');
} 

do_catchsql_test 7.2 {
  BEGIN;
    UPDATE ft2 SET rowid=2 WHERE rowid=1;
} {1 {constraint failed}} 

do_execsql_test 7.3 {
  COMMIT;
  INSERT INTO ft2(ft2) VALUES('integrity-check');
} {}

do_execsql_test 7.4 {
  SELECT * FROM ft2;
} {{a b c} {a b d}}

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 8.1 {
  CREATE VIRTUAL TABLE ft2 USING fts5(content);
  INSERT INTO ft2(rowid, content) VALUES(1, 'a b');
}

do_execsql_test 8.2 {
  BEGIN;
    INSERT INTO ft2(rowid, content) VALUES(4, 'a x');
}

do_execsql_test 8.3 {
  INSERT INTO ft2(ft2) VALUES('integrity-check');
}

#-------------------------------------------------------------------------
# Check that the "table function" syntax works.
#
reset_db
do_execsql_test 9.1 {
  CREATE VIRTUAL TABLE ft2 USING fts5(content);
  INSERT INTO ft2(rowid, content) VALUES(1, 'a b');
  INSERT INTO ft2(rowid, content) VALUES(2, 'a b c d');
  INSERT INTO ft2(rowid, content) VALUES(3, 'c d e f');
}

do_execsql_test 9.2 {
  SELECT rowid FROM ft2('a');
} {1 2}

do_execsql_test 9.3 {
  SELECT rowid FROM ft2('b AND c');
} {2}

#-------------------------------------------------------------------------
#
do_execsql_test 10.0 {
  CREATE VIRTUAL TABLE t3 USING fts5(a, b, c);
  INSERT INTO t3 VALUES('bac aab bab', 'c bac c', 'acb aba abb'); -- 1
  INSERT INTO t3 VALUES('bab abc c', 'acb c abb', 'c aaa c');     -- 2
}

do_execsql_test 10.1 {
  SELECT rowid FROM t3('c: c*');
} {2}

#-------------------------------------------------------------------------
# Test that character 0x1A is allowed in fts5 barewords.
#
do_test 11.0 {
  execsql "CREATE VIRTUAL TABLE t4 USING fts5(x, tokenize=\"ascii tokenchars '\x1A'\")"
  execsql "
    INSERT INTO t4 VALUES('a b c \x1A');
    INSERT INTO t4 VALUES('a b c d\x1A');
    INSERT INTO t4 VALUES('a b c \x1Ad');
    INSERT INTO t4 VALUES('a b c d');
  "
} {}

do_test 11.1 {
  execsql "SELECT rowid FROM t4('\x1A')"
} {1}
do_test 11.2 {
  execsql "SELECT rowid FROM t4('\x1A*')"
} {1 3}
do_test 11.3 {
  execsql "SELECT rowid FROM t4('d\x1A')"
} {2}

do_test 11.4 {
  catchsql "SELECT rowid FROM t4('d\x1B')"
} {/fts5: syntax error/}
do_test 11.5 {
  catchsql "SELECT rowid FROM t4('d\x19')"
} {/fts5: syntax error/}


finish_test

proc usage {} {
  puts stderr "$::argv0 ?OPTIONS? DATABASE FILE1..."
  puts stderr ""
  puts stderr "Options are"
  puts stderr "  -fts5"
  puts stderr "  -fts4"
  puts stderr "  -colsize <list of column sizes>"
  puts stderr {
This script is designed to create fts4/5 tables with more than one column.
The -colsize option should be set to a Tcl list of integer values, one for
each column in the table. Each value is the number of tokens that will be
inserted into the column value for each row. For example, setting the -colsize
option to "5 10" creates an FTS table with 2 columns, with roughly 5 and 10
tokens per row in each, respectively.

Each "FILE" argument should be a text file. The contents of these text files is
split on whitespace characters to form a list of tokens. The first N1 tokens
are used for the first column of the first row, where N1 is the first element
of the -colsize list. The next N2 are used for the second column of the first
row, and so on. Rows are added to the table until the entire list of tokens
is exhausted.
}
  exit -1
}

set O(aColsize)       [list 10 10 10]
set O(tblname)        t1
set O(fts)            fts5


set options_with_values {-colsize}

for {set i 0} {$i < [llength $argv]} {incr i} {
  set opt [lindex $argv $i]
  if {[string range $opt 0 0]!="-"} break

  if {[lsearch $options_with_values $opt]>=0} {
    incr i
    if {$i==[llength $argv]} usage
    set val [lindex $argv $i]
  }

  switch -- $opt {
    -colsize {
      set O(aColSize) $val
    }

    -fts4 {
      set O(fts) fts4
    }

    -fts5 {
      set O(fts) fts5
    }
  }
}

if {$i > [llength $argv]-2} usage
set O(db) [lindex $argv $i]
set O(files) [lrange $argv [expr $i+1] end]

foreach {k v} [lrange $argv 0 end-2] {
  switch -- $k {
    -colsize {
      set O(aColSize) $v
    }

    -colsize {
      set O(aColSize) $v
    }
  }

}

sqlite3 db $O(db)
load_static_extension db fts5


# Create the FTS table in the db. Return a list of the table columns.
#
proc create_table {} {
  global O
  set cols [list a b c d e f g h i j k l m n o p q r s t u v w x y z]

  set nCol [llength $O(aColsize)]
  set cols [lrange $cols 0 [expr $nCol-1]]

  set sql    "CREATE VIRTUAL TABLE IF NOT EXISTS $O(tblname) USING $O(fts) ("
  append sql [join $cols ,]
  append sql ");"

  db eval $sql
  return $cols
}

# Return a list of tokens from the named file.
#
proc readfile {file} {
  set fd [open $file]
  set data [read $fd]
  close $fd
  split $data
}


# Load all the data into a big list of tokens.
#
set tokens [list]
foreach f $O(files) {
  set tokens [concat $tokens [readfile $f]]
}

set N [llength $tokens]
set i 0
set cols [create_table]
set sql "INSERT INTO $O(tblname) VALUES(\$[lindex $cols 0]"
foreach c [lrange $cols 1 end] {
  append sql ", \$$c"
}
append sql ")"

db eval BEGIN
  while {$i < $N} {
    foreach c $cols s $O(aColsize) {
      set $c [lrange $tokens $i [expr $i+$s-1]]
      incr i $s
    }
    db eval $sql
  }
db eval COMMIT

#   rtree-5.*: Test DELETE
#   rtree-6.*: Test UPDATE
#   rtree-7.*: Test renaming an r-tree table.
#   rtree-8.*: Test constrained scans of r-tree data.
#
#   rtree-12.*: Test that on-conflict clauses are supported.
#   rtree-13.*: Test that bug [d2889096e7bdeac6d] has been fixed.
#   rtree-14.*: Test if a non-integer is inserted into the PK column of an
#               r-tree table, it is converted to an integer before being
#               inserted. Also that if a non-numeric is inserted into one
#               of the min/max dimension columns, it is converted to the
#               required type before being inserted.
#

ifcapable !rtree {
  finish_test
  return
}

  WITH r(x) AS (
    SELECT 1 UNION ALL
    SELECT 2 UNION ALL
    SELECT 3
  )
  SELECT * FROM r CROSS JOIN t9 WHERE id=x;
} {1 1 0.0 0.0 2 2 0.0 0.0}

#-------------------------------------------------------------------------
# Test if a non-integer is inserted into the PK column of an r-tree
# table, it is converted to an integer before being inserted. Also
# that if a non-numeric is inserted into one of the min/max dimension
# columns, it is converted to the required type before being inserted.
#
do_execsql_test 14.1 {
  CREATE VIRTUAL TABLE t10 USING rtree(ii, x1, x2);
}

do_execsql_test 14.2 {
  INSERT INTO t10 VALUES(NULL,   1, 2);
  INSERT INTO t10 VALUES(NULL,   2, 3);
  INSERT INTO t10 VALUES('4xxx', 3, 4);
  INSERT INTO t10 VALUES(5.0,    4, 5);
  INSERT INTO t10 VALUES(6.4,    5, 6);
}
do_execsql_test 14.3 {
  SELECT * FROM t10;
} {
  1 1.0 2.0   2 2.0 3.0   4 3.0 4.0   5 4.0 5.0   6 5.0 6.0
}

do_execsql_test 14.4 {
  DELETE FROM t10;
  INSERT INTO t10 VALUES(1, 'one', 'two');
  INSERT INTO t10 VALUES(2, '52xyz', '81...');
}
do_execsql_test 14.5 {
  SELECT * FROM t10;
} {
  1 0.0 0.0
  2 52.0 81.0
}

do_execsql_test 14.4 {
  DROP TABLE t10;
  CREATE VIRTUAL TABLE t10 USING rtree_i32(ii, x1, x2);
  INSERT INTO t10 VALUES(1, 'one', 'two');
  INSERT INTO t10 VALUES(2, '52xyz', '81...');
  INSERT INTO t10 VALUES(3, 42.3, 49.9);
}
do_execsql_test 14.5 {
  SELECT * FROM t10;
} {
  1 0 0
  2 52 81
  3 42 49
}

finish_test

** compiled without mutexes (SQLITE_THREADSAFE=0).
*/
void sqlite3MemoryBarrier(void){
#if defined(SQLITE_MEMORY_BARRIER)
  SQLITE_MEMORY_BARRIER;
#elif defined(__GNUC__)
  __sync_synchronize();
#elif !defined(SQLITE_DISABLE_INTRINSIC) && \
      defined(_MSC_VER) && _MSC_VER>=1300
  _ReadWriteBarrier();
#elif defined(MemoryBarrier)
  MemoryBarrier();
#endif
}

/*
** Initialize and deinitialize the mutex subsystem.
*/

    /* Code that appears at the end of the integrity check.  If no error
    ** messages have been generated, output OK.  Otherwise output the
    ** error message
    */
    static const int iLn = VDBE_OFFSET_LINENO(2);
    static const VdbeOpList endCode[] = {
      { OP_AddImm,      1, 0,        0},    /* 0 */
      { OP_If,          1, 0,        0},    /* 1 */
      { OP_String8,     0, 3,        0},    /* 2 */
      { OP_ResultRow,   3, 1,        0},
    };

    int isQuick = (sqlite3Tolower(zLeft[0])=='q');

    /* If the PRAGMA command was of the form "PRAGMA <db>.integrity_check",
    ** then iDb is set to the index of the database identified by <db>.

          sqlite3VdbeAddOp3(v, OP_Concat, 3, 2, 7);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 7, 1);
        }
#endif /* SQLITE_OMIT_BTREECOUNT */
      } 
    }
    addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode, iLn);
    sqlite3VdbeChangeP2(v, addr, -mxErr);
    sqlite3VdbeJumpHere(v, addr+1);
    sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
  }
  break;
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_UTF16
  /*
  **   PRAGMA encoding

    int addr;
    int iLimit;
    if( pSelect->iOffset ){
      iLimit = pSelect->iOffset+1;
    }else{
      iLimit = pSelect->iLimit;
    }
    addr = sqlite3VdbeAddOp3(v, OP_IfNotZero, iLimit, 0, 1); VdbeCoverage(v);
    sqlite3VdbeAddOp1(v, OP_Last, pSort->iECursor);
    sqlite3VdbeAddOp1(v, OP_Delete, pSort->iECursor);
    sqlite3VdbeJumpHere(v, addr);
  }
}

/*
** Add code to implement the OFFSET
*/
static void codeOffset(
  Vdbe *v,          /* Generate code into this VM */
  int iOffset,      /* Register holding the offset counter */
  int iContinue     /* Jump here to skip the current record */
){
  if( iOffset>0 ){

    sqlite3VdbeAddOp3(v, OP_IfPos, iOffset, iContinue, 1); VdbeCoverage(v);

    VdbeComment((v, "OFFSET"));

  }
}

/*
** Add code that will check to make sure the N registers starting at iMem
** form a distinct entry.  iTab is a sorting index that holds previously
** seen combinations of the N values.  A new entry is made in iTab

** the reuse of the same limit and offset registers across multiple
** SELECT statements.
*/
static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
  Vdbe *v = 0;
  int iLimit = 0;
  int iOffset;
  int n;
  if( p->iLimit ) return;

  /* 
  ** "LIMIT -1" always shows all rows.  There is some
  ** controversy about what the correct behavior should be.
  ** The current implementation interprets "LIMIT 0" to mean
  ** no rows.

    }
    if( p->pOffset ){
      p->iOffset = iOffset = ++pParse->nMem;
      pParse->nMem++;   /* Allocate an extra register for limit+offset */
      sqlite3ExprCode(pParse, p->pOffset, iOffset);
      sqlite3VdbeAddOp1(v, OP_MustBeInt, iOffset); VdbeCoverage(v);
      VdbeComment((v, "OFFSET counter"));

      sqlite3VdbeAddOp3(v, OP_SetIfNotPos, iOffset, iOffset, 0);

      sqlite3VdbeAddOp3(v, OP_Add, iLimit, iOffset, iOffset+1);
      VdbeComment((v, "LIMIT+OFFSET"));

      sqlite3VdbeAddOp3(v, OP_SetIfNotPos, iLimit, iOffset+1, -1);

    }
  }
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Return the appropriate collating sequence for the iCol-th column of

      }
      p->pPrior = 0;
      p->iLimit = pPrior->iLimit;
      p->iOffset = pPrior->iOffset;
      if( p->iLimit ){
        addr = sqlite3VdbeAddOp1(v, OP_IfNot, p->iLimit); VdbeCoverage(v);
        VdbeComment((v, "Jump ahead if LIMIT reached"));
        if( p->iOffset ){
          sqlite3VdbeAddOp3(v, OP_SetIfNotPos, p->iOffset, p->iOffset, 0);
          sqlite3VdbeAddOp3(v, OP_Add, p->iLimit, p->iOffset, p->iOffset+1);
          sqlite3VdbeAddOp3(v, OP_SetIfNotPos, p->iLimit, p->iOffset+1, -1);
        }
      }
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &dest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      p->nSelectRow += pPrior->nSelectRow;

*/
#if !defined(SQLITE_DISABLE_INTRINSIC)
#  if defined(_MSC_VER) && _MSC_VER>=1300
#    if !defined(_WIN32_WCE)
#      include <intrin.h>
#      pragma intrinsic(_byteswap_ushort)
#      pragma intrinsic(_byteswap_ulong)
#      pragma intrinsic(_ReadWriteBarrier)
#    else
#      include <cmnintrin.h>
#    endif
#  endif
#endif

/*

  if( pIn1->u.i<pIn2->u.i){
    pIn1->u.i = pIn2->u.i;
  }
  break;
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */

/* Opcode: IfPos P1 P2 P3 * *
** Synopsis: if r[P1]>0 then r[P1]-=P3, goto P2
**
** Register P1 must contain an integer.
** If the value of register P1 is 1 or greater, subtract P3 from the
** value in P1 and jump to P2.
**
** If the initial value of register P1 is less than 1, then the
** value is unchanged and control passes through to the next instruction.
*/
case OP_IfPos: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken( pIn1->u.i>0, 2);
  if( pIn1->u.i>0 ){
    pIn1->u.i -= pOp->p3;
    goto jump_to_p2;
  }
  break;
}

/* Opcode: SetIfNotPos P1 P2 P3 * *
** Synopsis: if r[P1]<=0 then r[P2]=P3
**
** Register P1 must contain an integer.
** If the value of register P1 is not positive (if it is less than 1) then
** set the value of register P2 to be the integer P3.
*/
case OP_SetIfNotPos: {        /* in1, in2 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );


  if( pIn1->u.i<=0 ){
    pOut = out2Prerelease(p, pOp);
    pOut->u.i = pOp->p3;
  }
  break;
}

/* Opcode: IfNotZero P1 P2 P3 * *
** Synopsis: if r[P1]!=0 then r[P1]-=P3, goto P2
**
** Register P1 must contain an integer.  If the content of register P1 is
** initially nonzero, then subtract P3 from the value in register P1 and
** jump to P2.  If register P1 is initially zero, leave it unchanged
** and fall through.
*/
case OP_IfNotZero: {        /* jump, in1 */
  pIn1 = &aMem[pOp->p1];
  assert( pIn1->flags&MEM_Int );
  VdbeBranchTaken(pIn1->u.i<0, 2);
  if( pIn1->u.i ){
     pIn1->u.i -= pOp->p3;
     goto jump_to_p2;
  }
  break;
}

/* Opcode: DecrJumpZero P1 P2 * * *
** Synopsis: if (--r[P1])==0 goto P2

/*
** Erase the eponymous virtual table instance associated with
** virtual table module pMod, if it exists.
*/
void sqlite3VtabEponymousTableClear(sqlite3 *db, Module *pMod){
  Table *pTab = pMod->pEpoTab;
  if( pTab!=0 ){
    sqlite3DeleteColumnNames(db, pTab);
    sqlite3VtabClear(db, pTab);
    sqlite3DbFree(db, pTab);
    pMod->pEpoTab = 0;
  }
}

          eExtraOp = WO_EQUIV;
        }
      }else{
        pDup = pExpr;
        pNew = pTerm;
      }
      exprCommute(pParse, pDup);

      pNew->leftCursor = iCur;
      pNew->u.leftColumn = iColumn;
      testcase( (prereqLeft | extraRight) != prereqLeft );
      pNew->prereqRight = prereqLeft | extraRight;
      pNew->prereqAll = prereqAll;
      pNew->eOperator = (operatorMask(pDup->op) + eExtraOp) & opMask;
    }

proc balanced_andor_tree {nEntry} {
  set tree [balanced_exprtree_structure $nEntry]
  set node "{[balanced_and_tree $nEntry]}"
  regsub -all AND $node OR node
  regsub -all xxx $tree $node tree
  return $tree
}

if 1 {

# Test that queries like "1 AND 2 AND 3 AND 4..." are transformed to 
# balanced trees by FTS.
#
for {set i 1} {$i < 100} {incr i} {
  do_test 1.$i {
    test_fts3expr2 [random_and_query $i]

set query [random_andor_query 12]
set result [balanced_andor_tree 12]
do_faultsim_test fts3expr3-fault-1 -faults oom-* -body {
  test_fts3expr2 $::query
} -test {
  faultsim_test_result [list 0 $::result]
}

}

#-------------------------------------------------------------------

foreach {tn expr res} {
  1 {1 OR 2 OR 3 OR 4}           {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} 
  2 {1 OR (2 AND 3 AND 4 AND 5)} 
    {OR {P 1} {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}}}
  3 {(2 AND 3 AND 4 AND 5) OR 1} 
    {OR {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}} {P 1}}

  4 {1 AND (2 OR 3 OR 4 OR 5)} 
    {AND {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}
  5 {(2 OR 3 OR 4 OR 5) AND 1} 
    {AND {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}

  6 {(2 OR 3 OR 4 OR 5) NOT 1} 
    {NOT {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}

  7 {1 NOT (2 OR 3 OR 4 OR 5)} 
    {NOT {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}

  8 {(1 OR 2 OR 3 OR 4) NOT (5 AND 6 AND 7 AND 8)}
    {NOT {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} {AND {AND {P 5} {P 6}} {AND {P 7} {P 8}}}}
} {
  do_test 5.1.$tn {
    test_fts3expr2 $expr
  } $res
}

set sqlite_fts3_enable_parentheses 0
finish_test

# 2015-10-06
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# 
# This file implements test cases for the [b65cb2c8d91f6685841d7d1e13b6]
# bug:  Correct handling of LIMIT and OFFSET on a UNION ALL query where
# the right-hand SELECT contains an ORDER BY in a subquery.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

ifcapable !compound {
  finish_test
  return
}

do_execsql_test offset1-1.1 {
  CREATE TABLE t1(a,b);
  INSERT INTO t1 VALUES(1,'a'),(2,'b'),(3,'c'),(4,'d'),(5,'e');
  CREATE TABLE t2(x,y);
  INSERT INTO t2 VALUES(8,'y'),(9,'z'),(6,'w'),(7,'x');
  SELECT count(*) FROM t1, t2;
} {20}

do_execsql_test offset1-1.2.0 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 0;
} {1 a 2 b 3 c}
do_execsql_test offset1-1.2.1 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 1;
} {2 b 3 c 4 d}
do_execsql_test offset1-1.2.2 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 2;
} {3 c 4 d 5 e}
do_execsql_test offset1-1.2.3 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 3;
} {4 d 5 e 6 w}
do_execsql_test offset1-1.2.4 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 4;
} {5 e 6 w 7 x}
do_execsql_test offset1-1.2.5 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 5;
} {6 w 7 x 8 y}
do_execsql_test offset1-1.2.6 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 6;
} {7 x 8 y 9 z}
do_execsql_test offset1-1.2.7 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 7;
} {8 y 9 z}
do_execsql_test offset1-1.2.8 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 8;
} {9 z}
do_execsql_test offset1-1.2.9 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 9;
} {}

do_execsql_test offset1-1.3.0 {
  SELECT * FROM t1 LIMIT 0;
} {}

do_execsql_test offset1-1.4.0 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 0 OFFSET 1;
} {}
do_execsql_test offset1-1.4.1 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 1 OFFSET 1;
} {2 b}
do_execsql_test offset1-1.4.2 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 2 OFFSET 1;
} {2 b 3 c}
do_execsql_test offset1-1.4.3 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 3 OFFSET 1;
} {2 b 3 c 4 d}
do_execsql_test offset1-1.4.4 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 4 OFFSET 1;
} {2 b 3 c 4 d 5 e}
do_execsql_test offset1-1.4.5 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 5 OFFSET 1;
} {2 b 3 c 4 d 5 e 6 w}
do_execsql_test offset1-1.4.6 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 6 OFFSET 1;
} {2 b 3 c 4 d 5 e 6 w 7 x}
do_execsql_test offset1-1.4.7 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 7 OFFSET 1;
} {2 b 3 c 4 d 5 e 6 w 7 x 8 y}
do_execsql_test offset1-1.4.8 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 8 OFFSET 1;
} {2 b 3 c 4 d 5 e 6 w 7 x 8 y 9 z}
do_execsql_test offset1-1.4.9 {
  SELECT a, b FROM t1
  UNION ALL
  SELECT * FROM (SELECT x, y FROM t2 ORDER BY y)
  LIMIT 9 OFFSET 1;
} {2 b 3 c 4 d 5 e 6 w 7 x 8 y 9 z}



finish_test

  WHERE word MATCH 'amstedam*' AND distance <= 100 AND top=20;
} {
  32 20
}

do_execsql_test 1.6 {
  SELECT word, distance, matchlen FROM demo 
  WHERE word MATCH 'amstedam*' AND distance <= 100
  ORDER BY distance, word;
} {
  amsterdam         100 9        amsterdama        100 9
  amsterdamania     100 9        amsterdamb        100 9
  amsterdamc        100 9        amsterdamd        100 9
  amsterdame        100 9        amsterdamf        100 9
  amsterdamg        100 9        amsterdamh        100 9

  amsterdami        100 9        amsterdamj        100 9
  amsterdamk        100 9        amsterdaml        100 9
  amsterdamlaan     100 9        amsterdamm        100 9
  amsterdammetje    100 9        amsterdamn        100 9
  amsterdamo        100 9        amsterdamp        100 9
  amsterdamq        100 9        amsterdamr        100 9
  amsterdams        100 9        amsterdamsestraat 100 9

  amsterdamt        100 9        amsterdamu        100 9
  amsterdamv        100 9        amsterdamw        100 9
  amsterdamweg      100 9        amsterdamx        100 9
  amsterdamy        100 9        amsterdamz        100 9
}

do_execsql_test 1.7 {
  SELECT word, distance, matchlen FROM demo 
  WHERE word MATCH 'amstedam*' AND distance <= 100 AND top=20
  ORDER BY distance, word;
} {
  amsterdam         100 9        amsterdama        100 9
  amsterdamania     100 9        amsterdamb        100 9
  amsterdamc        100 9        amsterdame        100 9
  amsterdamf        100 9        amsterdamg        100 9
  amsterdamh        100 9        amsterdami        100 9
  amsterdamm        100 9        amsterdammetje    100 9
  amsterdamn        100 9        amsterdamo        100 9
  amsterdamp        100 9        amsterdamu        100 9
  amsterdamv        100 9        amsterdamw        100 9
  amsterdamweg      100 9        amsterdamy        100 9
}


finish_test

    #
    # NOTE: Due to limits on legal characters for file names imposed by
    #       Windows, we must skip the final two tests here (i.e. the
    #       question mark is illegal in a file name on Windows).
    #
    if {$tn>14} break

    #
    # NOTE: When running on Tcl 8.6 (or higher?) on Windows, a colon within
    #       the file name no longer tries to access an alternate data stream
    #       (ADS) named "test.db" for the "http" file, causing some spurious
    #       failures of this test.
    #
    if {$tn==12 && $::tcl_version>=8.6} continue

    #
    # NOTE: On Windows, we need to account for the fact that the current
    #       directory does not start with a forward slash.
    #
    set uri  [string map [list PWD/ /[test_pwd /]] $uri]
  } else {
    set uri  [string map [list PWD/ [test_pwd /]] $uri]