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Overview
Comment:Add a way for virtual tables to return the expected number of rows for a scan (not just the overall cost) to SQLite. Have the rtree module make use of this.
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SHA1:5a3cfd747a85480d215784817c3821d87ecfa2f7
User & Date: dan 2013-11-11 19:01:33
Context
2013-11-11
19:56
Fix typos in compile and run-time tests of the sqlite library version number in rtree.c. check-in: f58d5701 user: dan tags: trunk
19:01
Add a way for virtual tables to return the expected number of rows for a scan (not just the overall cost) to SQLite. Have the rtree module make use of this. check-in: 5a3cfd74 user: dan tags: trunk
16:55
Remove unreachable code, replacing it in most cases with assert() or NEVER() macros. check-in: 924d63b2 user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to ext/rtree/rtree.c.

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











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


  /* List of nodes removed during a CondenseTree operation. List is
  ** linked together via the pointer normally used for hash chains -
  ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree 
  ** headed by the node (leaf nodes have RtreeNode.iNode==0).
  */
  RtreeNode *pDeleted;
................................................................................
      assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCell<NCELL(pCsr->pNode) );
    }
  }

  rtreeRelease(pRtree);
  return rc;
}














/*
** Rtree virtual table module xBestIndex method. There are three
** table scan strategies to choose from (in order from most to 
** least desirable):
**
**   idxNum     idxStr        Strategy
................................................................................
**   ----------------------
**
** The second of each pair of bytes identifies the coordinate column
** to which the constraint applies. The leftmost coordinate column
** is 'a', the second from the left 'b' etc.
*/
static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){

  int rc = SQLITE_OK;
  int ii;


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

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

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

      /* This strategy involves a two rowid lookups on an B-Tree structures
      ** and then a linear search of an R-Tree node. This should be 
      ** considered almost as quick as a direct rowid lookup (for which 
      ** sqlite uses an internal cost of 0.0).

      */ 
      pIdxInfo->estimatedCost = 10.0;

      return SQLITE_OK;
    }

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

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


  pIdxInfo->estimatedCost = (2000000.0 / (double)(iIdx + 1));


  return rc;
}

/*
** Return the N-dimensional volumn of the cell stored in *p.
*/
static RtreeDValue cellArea(Rtree *pRtree, RtreeCell *p){
................................................................................
  );
  if( zSql ){
    rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }
  return rc;
}
































static sqlite3_module rtreeModule = {
  0,                          /* iVersion */
  rtreeCreate,                /* xCreate - create a table */
  rtreeConnect,               /* xConnect - connect to an existing table */
  rtreeBestIndex,             /* xBestIndex - Determine search strategy */
  rtreeDisconnect,            /* xDisconnect - Disconnect from a table */
................................................................................
  appStmt[3] = &pRtree->pReadRowid;
  appStmt[4] = &pRtree->pWriteRowid;
  appStmt[5] = &pRtree->pDeleteRowid;
  appStmt[6] = &pRtree->pReadParent;
  appStmt[7] = &pRtree->pWriteParent;
  appStmt[8] = &pRtree->pDeleteParent;


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







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

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

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

  /* List of nodes removed during a CondenseTree operation. List is
  ** linked together via the pointer normally used for hash chains -
  ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree 
  ** headed by the node (leaf nodes have RtreeNode.iNode==0).
  */
  RtreeNode *pDeleted;
................................................................................
      assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCell<NCELL(pCsr->pNode) );
    }
  }

  rtreeRelease(pRtree);
  return rc;
}

/*
** Set the pIdxInfo->estimatedRows variable to nRow. Unless this
** extension is currently being used by a version of SQLite too old to
** support estimatedRows. In that case this function is a no-op.
*/
static void setEstimatedRows(sqlite3_index_info *pIdxInfo, i64 nRow){
#if SQLITE_VERSION_NUMBER>=308002
  if( sqlite3_libversion_number()>=300802 ){
    pIdxInfo->estimatedRows = nRow;
  }
#endif
}

/*
** Rtree virtual table module xBestIndex method. There are three
** table scan strategies to choose from (in order from most to 
** least desirable):
**
**   idxNum     idxStr        Strategy
................................................................................
**   ----------------------
**
** The second of each pair of bytes identifies the coordinate column
** to which the constraint applies. The leftmost coordinate column
** is 'a', the second from the left 'b' etc.
*/
static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  Rtree *pRtree = (Rtree*)tab;
  int rc = SQLITE_OK;
  int ii;
  i64 nRow;                       /* Estimated rows returned by this scan */

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


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

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

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

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

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


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

  return rc;
}

/*
** Return the N-dimensional volumn of the cell stored in *p.
*/
static RtreeDValue cellArea(Rtree *pRtree, RtreeCell *p){
................................................................................
  );
  if( zSql ){
    rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
    sqlite3_free(zSql);
  }
  return rc;
}

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

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

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

  return rc;
}

static sqlite3_module rtreeModule = {
  0,                          /* iVersion */
  rtreeCreate,                /* xCreate - create a table */
  rtreeConnect,               /* xConnect - connect to an existing table */
  rtreeBestIndex,             /* xBestIndex - Determine search strategy */
  rtreeDisconnect,            /* xDisconnect - Disconnect from a table */
................................................................................
  appStmt[3] = &pRtree->pReadRowid;
  appStmt[4] = &pRtree->pWriteRowid;
  appStmt[5] = &pRtree->pDeleteRowid;
  appStmt[6] = &pRtree->pReadParent;
  appStmt[7] = &pRtree->pWriteParent;
  appStmt[8] = &pRtree->pDeleteParent;

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

Changes to ext/rtree/rtree6.test.

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  0 1 1 {SEARCH TABLE t2 USING INTEGER PRIMARY KEY (rowid=?)}
}

do_eqp_test rtree6.2.4 {
  SELECT * FROM t1,t2 WHERE v=10 and x1<10 and x2>10
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 2:CaEb} 
  0 1 1 {SCAN TABLE t2}
}

do_eqp_test rtree6.2.5 {
  SELECT * FROM t1,t2 WHERE k=ii AND x1<v
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 2:} 
  0 1 1 {SEARCH TABLE t2 USING INTEGER PRIMARY KEY (rowid=?)}







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  0 1 1 {SEARCH TABLE t2 USING INTEGER PRIMARY KEY (rowid=?)}
}

do_eqp_test rtree6.2.4 {
  SELECT * FROM t1,t2 WHERE v=10 and x1<10 and x2>10
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 2:CaEb} 
  0 1 1 {SEARCH TABLE t2 USING AUTOMATIC COVERING INDEX (v=?)}
}

do_eqp_test rtree6.2.5 {
  SELECT * FROM t1,t2 WHERE k=ii AND x1<v
} {
  0 0 0 {SCAN TABLE t1 VIRTUAL TABLE INDEX 2:} 
  0 1 1 {SEARCH TABLE t2 USING INTEGER PRIMARY KEY (rowid=?)}

Added ext/rtree/rtreeC.test.

































































































































































































































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# 2011 March 2
#
# 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.
#
#***********************************************************************
# Make sure the rtreenode() testing function can handle entries with
# 64-bit rowids.
# 

if {![info exists testdir]} {
  set testdir [file join [file dirname [info script]] .. .. test]
} 
source $testdir/tester.tcl
ifcapable !rtree { finish_test ; return }
set testprefix rtreeC

do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE r_tree USING rtree(id, min_x, max_x, min_y, max_y);
  CREATE TABLE t(x, y);
}

do_eqp_test 1.1 {
  SELECT * FROM r_tree, t 
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND t.x<=max_y
} {
  0 0 1 {SCAN TABLE t}
  0 1 0 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 1.2 {
  SELECT * FROM t, r_tree
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND t.x<=max_y
} {
  0 0 0 {SCAN TABLE t}
  0 1 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 1.3 {
  SELECT * FROM t, r_tree
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND ?<=max_y
} {
  0 0 0 {SCAN TABLE t}
  0 1 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 1.5 {
  SELECT * FROM t, r_tree
} {
  0 0 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:}
  0 1 0 {SCAN TABLE t} 
}

do_execsql_test 2.0 {
  INSERT INTO t VALUES(0, 0);
  INSERT INTO t VALUES(0, 1);
  INSERT INTO t VALUES(0, 2);
  INSERT INTO t VALUES(0, 3);
  INSERT INTO t VALUES(0, 4);
  INSERT INTO t VALUES(0, 5);
  INSERT INTO t VALUES(0, 6);
  INSERT INTO t VALUES(0, 7);
  INSERT INTO t VALUES(0, 8);
  INSERT INTO t VALUES(0, 9);

  INSERT INTO t SELECT x+1, y FROM t;
  INSERT INTO t SELECT x+2, y FROM t;
  INSERT INTO t SELECT x+4, y FROM t;
  INSERT INTO r_tree SELECT NULL, x-1, x+1, y-1, y+1 FROM t;
  ANALYZE;
}

db close
sqlite3 db test.db

do_eqp_test 2.1 {
  SELECT * FROM r_tree, t 
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND t.x<=max_y
} {
  0 0 1 {SCAN TABLE t}
  0 1 0 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 2.2 {
  SELECT * FROM t, r_tree
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND t.x<=max_y
} {
  0 0 0 {SCAN TABLE t}
  0 1 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 2.3 {
  SELECT * FROM t, r_tree
  WHERE t.x>=min_x AND t.x<=max_x AND t.y>=min_y AND ?<=max_y
} {
  0 0 0 {SCAN TABLE t}
  0 1 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:DdBcDbBa}
}

do_eqp_test 2.5 {
  SELECT * FROM t, r_tree
} {
  0 0 1 {SCAN TABLE r_tree VIRTUAL TABLE INDEX 2:}
  0 1 0 {SCAN TABLE t} 
}

finish_test

Changes to src/sqlite.h.in.

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5294
5295
5296












5297
5298
5299
5300
5301
5302
5303
....
5314
5315
5316
5317
5318
5319
5320
5321

5322
5323
5324
5325
5326
5327
5328
** ^[sqlite3_free()] is used to free idxPtr if and only if
** needToFreeIdxPtr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of doing the
** particular lookup.  A full scan of a table with N entries should have
** a cost of N.  A binary search of a table of N entries should have a
** cost of approximately log(N).












*/
struct sqlite3_index_info {
  /* Inputs */
  int nConstraint;           /* Number of entries in aConstraint */
  struct sqlite3_index_constraint {
     int iColumn;              /* Column on left-hand side of constraint */
     unsigned char op;         /* Constraint operator */
................................................................................
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
    unsigned char omit;      /* Do not code a test for this constraint */
  } *aConstraintUsage;
  int idxNum;                /* Number used to identify the index */
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;      /* Estimated cost of using this index */

};

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







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|
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>
>
>
>
>
>
>
>
>
>
>
>







 







|
>







5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
....
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
** ^[sqlite3_free()] is used to free idxPtr if and only if
** needToFreeIdxPtr is true.
**
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** ^The estimatedCost value is an estimate of the cost of a particular
** strategy. A cost of N indicates that the cost of the strategy is similar
** to a linear scan of an SQLite table with N rows. A cost of log(N) 
** indicates that the expense of the operation is similar to that of a
** binary search on a unique indexed field of an SQLite table with N rows.
**
** ^The estimatedRows value is an estimate of the number of rows that
** will be returned by the strategy.
**
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
** structure for SQLite version 3.8.2. If a virtual table extension is
** used with an SQLite version earlier than 3.8.2, the results of attempting 
** to read or write the estimatedRows field are undefined (but are likely 
** to included crashing the application). The estimatedRows field should
** therefore only be used if [sqlite3_libversion_number()] returns a
** value greater than or equal to 3008002.
*/
struct sqlite3_index_info {
  /* Inputs */
  int nConstraint;           /* Number of entries in aConstraint */
  struct sqlite3_index_constraint {
     int iColumn;              /* Column on left-hand side of constraint */
     unsigned char op;         /* Constraint operator */
................................................................................
    int argvIndex;           /* if >0, constraint is part of argv to xFilter */
    unsigned char omit;      /* Do not code a test for this constraint */
  } *aConstraintUsage;
  int idxNum;                /* Number used to identify the index */
  char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
  int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
  int orderByConsumed;       /* True if output is already ordered */
  double estimatedCost;           /* Estimated cost of using this index */
  sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
};

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

Changes to src/where.c.

1974
1975
1976
1977
1978
1979
1980

1981
1982
1983
1984
1985
1986
1987
....
4783
4784
4785
4786
4787
4788
4789

4790
4791
4792
4793
4794
4795
4796
....
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
       p->aConstraintUsage[i].argvIndex,
       p->aConstraintUsage[i].omit);
  }
  sqlite3DebugPrintf("  idxNum=%d\n", p->idxNum);
  sqlite3DebugPrintf("  idxStr=%s\n", p->idxStr);
  sqlite3DebugPrintf("  orderByConsumed=%d\n", p->orderByConsumed);
  sqlite3DebugPrintf("  estimatedCost=%g\n", p->estimatedCost);

}
#else
#define TRACE_IDX_INPUTS(A)
#define TRACE_IDX_OUTPUTS(A)
#endif

#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
................................................................................
    memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
    if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
    pIdxInfo->idxStr = 0;
    pIdxInfo->idxNum = 0;
    pIdxInfo->needToFreeIdxStr = 0;
    pIdxInfo->orderByConsumed = 0;
    pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;

    rc = vtabBestIndex(pParse, pTab, pIdxInfo);
    if( rc ) goto whereLoopAddVtab_exit;
    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
    pNew->prereq = 0;
    mxTerm = -1;
    assert( pNew->nLSlot>=nConstraint );
    for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;
................................................................................
      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
                                     && pIdxInfo->orderByConsumed);
      pNew->rSetup = 0;
      pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);
      /* TUNING: Every virtual table query returns 25 rows */
      pNew->nOut = 46;  assert( 46==sqlite3LogEst(25) );
      whereLoopInsert(pBuilder, pNew);
      if( pNew->u.vtab.needFree ){
        sqlite3_free(pNew->u.vtab.idxStr);
        pNew->u.vtab.needFree = 0;
      }
    }
  }  







>







 







>







 







|
<







1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
....
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
....
4844
4845
4846
4847
4848
4849
4850
4851

4852
4853
4854
4855
4856
4857
4858
       p->aConstraintUsage[i].argvIndex,
       p->aConstraintUsage[i].omit);
  }
  sqlite3DebugPrintf("  idxNum=%d\n", p->idxNum);
  sqlite3DebugPrintf("  idxStr=%s\n", p->idxStr);
  sqlite3DebugPrintf("  orderByConsumed=%d\n", p->orderByConsumed);
  sqlite3DebugPrintf("  estimatedCost=%g\n", p->estimatedCost);
  sqlite3DebugPrintf("  estimatedRows=%lld\n", p->estimatedRows);
}
#else
#define TRACE_IDX_INPUTS(A)
#define TRACE_IDX_OUTPUTS(A)
#endif

#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
................................................................................
    memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
    if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
    pIdxInfo->idxStr = 0;
    pIdxInfo->idxNum = 0;
    pIdxInfo->needToFreeIdxStr = 0;
    pIdxInfo->orderByConsumed = 0;
    pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
    pIdxInfo->estimatedRows = 25;
    rc = vtabBestIndex(pParse, pTab, pIdxInfo);
    if( rc ) goto whereLoopAddVtab_exit;
    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
    pNew->prereq = 0;
    mxTerm = -1;
    assert( pNew->nLSlot>=nConstraint );
    for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;
................................................................................
      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
      pIdxInfo->needToFreeIdxStr = 0;
      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
                                     && pIdxInfo->orderByConsumed);
      pNew->rSetup = 0;
      pNew->rRun = sqlite3LogEstFromDouble(pIdxInfo->estimatedCost);
      pNew->nOut = sqlite3LogEst(pIdxInfo->estimatedRows);

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