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SQLite training in Houston TX on 2019-11-05 (details)
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Overview
Comment:Build internal data structures appropriately for WITHOUT ROWID tables.
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Timelines: family | ancestors | descendants | both | omit-rowid
Files: files | file ages | folders
SHA1: 35a3606071685aa5196951f4bdddb136589ea216
User & Date: drh 2013-10-23 00:32:58
Context
2013-10-23
01:57
Some simple inserts and queries working on WITHOUT ROWID tables. check-in: 3f8016de user: drh tags: omit-rowid
00:32
Build internal data structures appropriately for WITHOUT ROWID tables. check-in: 35a36060 user: drh tags: omit-rowid
2013-10-22
18:01
The Index object now has nKeyCol and nColumn. nColumn is the total number of columns and nKeyCol is the number of key columns. Currently these always differ by one. Refactor aiColumn[] to be of type i16 instead of int. check-in: a106ce86 user: drh tags: omit-rowid
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/build.c.

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*/
static void freeIndex(sqlite3 *db, Index *p){
#ifndef SQLITE_OMIT_ANALYZE
  sqlite3DeleteIndexSamples(db, p);
#endif
  sqlite3ExprDelete(db, p->pPartIdxWhere);
  sqlite3DbFree(db, p->zColAff);

  sqlite3DbFree(db, p);
}

/*
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
................................................................................
    */
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
    if( isView || isVirtual ){
      sqlite3VdbeAddOp2(v, OP_Integer, 0, reg2);
    }else
#endif
    {

      sqlite3VdbeAddOp2(v, OP_CreateTable, iDb, reg2);
    }
    sqlite3OpenMasterTable(pParse, iDb);
    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, reg1);
    sqlite3VdbeAddOp2(v, OP_Null, 0, reg3);
    sqlite3VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeAddOp0(v, OP_Close);
................................................................................
   && zType && sqlite3StrICmp(zType, "INTEGER")==0
   && sortOrder==SQLITE_SO_ASC
  ){
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;

  }else if( autoInc ){
#ifndef SQLITE_OMIT_AUTOINCREMENT
    sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
       "INTEGER PRIMARY KEY");
#endif
  }else{
    Index *p;
................................................................................
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
  sqlite3_snprintf(n-k, &zStmt[k], "%s", zEnd);
  return zStmt;
}


























/*
** Estimate the total row width for a table.
*/
static void estimateTableWidth(Table *pTab){
  unsigned wTable = 0;
  const Column *pTabCol;
................................................................................
  for(i=0; i<pIdx->nColumn; i++){
    i16 x = pIdx->aiColumn[i];
    assert( x<pIdx->pTable->nCol );
    wIndex += x<0 ? 1 : aCol[pIdx->aiColumn[i]].szEst;
  }
  pIdx->szIdxRow = sqlite3LogEst(wIndex*4);
}
































































































/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
**
** The table structure that other action routines have been building
** is added to the internal hash tables, assuming no errors have
................................................................................
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

  if( tabOpts & TF_WithoutRowid ){
    if( (p->tabFlags & TF_HasPrimaryKey)==0 ){
      sqlite3ErrorMsg(pParse, "no PRIMARY KEY for table %s", p->zName);
    }
    p->tabFlags |= TF_WithoutRowid;


  }

  iDb = sqlite3SchemaToIndex(db, p->pSchema);

#ifndef SQLITE_OMIT_CHECK
  /* Resolve names in all CHECK constraint expressions.
  */
................................................................................
){
  Index *pRet = 0;     /* Pointer to return */
  Table *pTab = 0;     /* Table to be indexed */
  Index *pIndex = 0;   /* The index to be created */
  char *zName = 0;     /* Name of the index */
  int nName;           /* Number of characters in zName */
  int i, j;
  Token nullId;        /* Fake token for an empty ID list */
  DbFixer sFix;        /* For assigning database names to pTable */
  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
  sqlite3 *db = pParse->db;
  Db *pDb;             /* The specific table containing the indexed database */
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
................................................................................
#endif

  /* If pList==0, it means this routine was called to make a primary
  ** key out of the last column added to the table under construction.
  ** So create a fake list to simulate this.
  */
  if( pList==0 ){
    nullId.z = pTab->aCol[pTab->nCol-1].zName;
    nullId.n = sqlite3Strlen30((char*)nullId.z);
    pList = sqlite3ExprListAppend(pParse, 0, 0);
    if( pList==0 ) goto exit_create_index;
    sqlite3ExprListSetName(pParse, pList, &nullId, 0);


    pList->a[0].sortOrder = (u8)sortOrder;
  }

  /* Figure out how many bytes of space are required to store explicitly
  ** specified collation sequence names.
  */
  for(i=0; i<pList->nExpr; i++){







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*/
static void freeIndex(sqlite3 *db, Index *p){
#ifndef SQLITE_OMIT_ANALYZE
  sqlite3DeleteIndexSamples(db, p);
#endif
  sqlite3ExprDelete(db, p->pPartIdxWhere);
  sqlite3DbFree(db, p->zColAff);
  if( p->isResized ) sqlite3DbFree(db, p->azColl);
  sqlite3DbFree(db, p);
}

/*
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
................................................................................
    */
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
    if( isView || isVirtual ){
      sqlite3VdbeAddOp2(v, OP_Integer, 0, reg2);
    }else
#endif
    {
      assert( sqlite3VdbeCurrentAddr(v) < 100 );
      pParse->addrCrTab = (u16)sqlite3VdbeAddOp2(v, OP_CreateTable, iDb, reg2);
    }
    sqlite3OpenMasterTable(pParse, iDb);
    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, reg1);
    sqlite3VdbeAddOp2(v, OP_Null, 0, reg3);
    sqlite3VdbeAddOp3(v, OP_Insert, 0, reg3, reg1);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeAddOp0(v, OP_Close);
................................................................................
   && zType && sqlite3StrICmp(zType, "INTEGER")==0
   && sortOrder==SQLITE_SO_ASC
  ){
    pTab->iPKey = iCol;
    pTab->keyConf = (u8)onError;
    assert( autoInc==0 || autoInc==1 );
    pTab->tabFlags |= autoInc*TF_Autoincrement;
    if( pList ) pParse->iPkSortOrder = pList->a[0].sortOrder;
  }else if( autoInc ){
#ifndef SQLITE_OMIT_AUTOINCREMENT
    sqlite3ErrorMsg(pParse, "AUTOINCREMENT is only allowed on an "
       "INTEGER PRIMARY KEY");
#endif
  }else{
    Index *p;
................................................................................
    memcpy(&zStmt[k], zType, len);
    k += len;
    assert( k<=n );
  }
  sqlite3_snprintf(n-k, &zStmt[k], "%s", zEnd);
  return zStmt;
}

/*
** Resize an Index object to hold N columns total.  Return SQLITE_OK
** on success and SQLITE_NOMEM on an OOM error.
*/
static int resizeIndexObject(sqlite3 *db, Index *pIdx, int N){
  char *zExtra;
  int nByte;
  if( pIdx->nColumn>=N ) return SQLITE_OK;
  assert( pIdx->isResized==0 );
  nByte = (sizeof(char*) + sizeof(i16) + 1)*N;
  zExtra = sqlite3DbMallocZero(db, nByte);
  if( zExtra==0 ) return SQLITE_NOMEM;
  memcpy(zExtra, pIdx->azColl, sizeof(char*)*pIdx->nColumn);
  pIdx->azColl = (char**)zExtra;
  zExtra += sizeof(char*)*N;
  memcpy(zExtra, pIdx->aiColumn, sizeof(i16)*pIdx->nColumn);
  pIdx->aiColumn = (i16*)zExtra;
  zExtra += sizeof(i16)*N;
  memcpy(zExtra, pIdx->aSortOrder, pIdx->nColumn);
  pIdx->aSortOrder = (u8*)zExtra;
  pIdx->nColumn = N;
  pIdx->isResized = 1;
  return SQLITE_OK;
}

/*
** Estimate the total row width for a table.
*/
static void estimateTableWidth(Table *pTab){
  unsigned wTable = 0;
  const Column *pTabCol;
................................................................................
  for(i=0; i<pIdx->nColumn; i++){
    i16 x = pIdx->aiColumn[i];
    assert( x<pIdx->pTable->nCol );
    wIndex += x<0 ? 1 : aCol[pIdx->aiColumn[i]].szEst;
  }
  pIdx->szIdxRow = sqlite3LogEst(wIndex*4);
}

/* Return true if value x is found any of the first nCol entries of aiCol[]
*/
static int hasColumn(const i16 *aiCol, int nCol, int x){
  while( nCol-- > 0 ) if( x==*(aiCol++) ) return 1;
  return 0;
}

/*
** The table pTab has a WITHOUT ROWID clause at the end.  Go through and
** make all the changes necessary to make this a WITHOUT ROWID table.
**
**     (1)  Convert the OP_CreateTable into an no-op.
**     (2)  Make sure all table columns are part of the PRIMARY KEY
**     (3)  Make sure all PRIMARY KEY columns are part of all UNIQUE
**          indices
*/
static void convertToWithoutRowidTable(Parse *pParse, Table *pTab){
  Index *pIdx;
  Index *pPk;
  int nPk;
  int i, j;
  sqlite3 *db = pParse->db;

  /* Convert the OP_CreateTable opcode that would normally create the
  ** root-page for the table into a OP_Null opcode.  This prevents the
  ** allocation of the root-page (which would never been used, as all
  ** content is stored in the primary-key index instead) and it causes
  ** a NULL value in the sqlite_master.rootpage field of the schema.
  */
  if( pParse->addrCrTab ){
    sqlite3VdbeGetOp(pParse->pVdbe, pParse->addrCrTab)->opcode = OP_Null;
  }

  /* Locate the PRIMARY KEY index.  Or, if this table was originally
  ** an INTEGER PRIMARY KEY table, create a new PRIMARY KEY index. 
  */
  if( pTab->iPKey>=0 ){
    ExprList *pList;
    pList = sqlite3ExprListAppend(pParse, 0, 0);
    if( pList==0 ) return;
    pList->a[0].zName = sqlite3DbStrDup(pParse->db,
                                        pTab->aCol[pTab->iPKey].zName);
    pList->a[0].sortOrder = pParse->iPkSortOrder;
    assert( pParse->pNewTable==pTab );
    pPk = sqlite3CreateIndex(pParse, 0, 0, 0, pList, pTab->keyConf, 0, 0, 0, 0);
    if( pPk==0 ) return;
    pTab->iPKey = -1;
  }
  for(pPk=pTab->pIndex; pPk && pPk->autoIndex<2; pPk=pPk->pNext){}
  assert( pPk!=0 );
  nPk = pPk->nKeyCol;

  /* Update the in-memory representation of all UNIQUE indices by converting
  ** the final rowid column into one or more columns of the PRIMARY KEY.
  */
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    int n;
    if( pIdx->autoIndex==2 ) continue;
    if( pIdx->nKeyCol==pTab->nCol ){
      pIdx->nColumn = pTab->nCol;
      continue;
    }
    for(i=n=0; i<nPk; i++){
      if( !hasColumn(pIdx->aiColumn, pIdx->nKeyCol, pPk->aiColumn[i]) ) n++;
    }
    if( resizeIndexObject(db, pIdx, pIdx->nKeyCol+n) ) return;
    for(i=0, j=pIdx->nKeyCol; i<nPk; i++){
      if( !hasColumn(pIdx->aiColumn, j, pPk->aiColumn[i]) ){
        assert( j<pPk->nColumn );
        pIdx->aiColumn[j] = pPk->aiColumn[i];
        pIdx->azColl[j] = pPk->azColl[i];
        j++;
      }
    }
    assert( pIdx->nColumn==j );
    assert( pIdx->nKeyCol+n==j );
  }

  /* Add all table columns to the PRIMARY KEY index
  */
  if( nPk<pTab->nCol ){
    if( resizeIndexObject(db, pPk, pTab->nCol) ) return;
    for(i=0, j=nPk; i<pTab->nCol; i++){
      if( !hasColumn(pPk->aiColumn, j, i) ){
        assert( j<pPk->nColumn );
        pPk->aiColumn[j] = i;
        pPk->azColl[j] = "BINARY";
        j++;
      }
    }
    assert( pPk->nColumn==j );
    assert( pTab->nCol==j );
  }
}

/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
**
** The table structure that other action routines have been building
** is added to the internal hash tables, assuming no errors have
................................................................................
  if( p==0 ) return;

  assert( !db->init.busy || !pSelect );

  if( tabOpts & TF_WithoutRowid ){
    if( (p->tabFlags & TF_HasPrimaryKey)==0 ){
      sqlite3ErrorMsg(pParse, "no PRIMARY KEY for table %s", p->zName);
    }else{
      p->tabFlags |= TF_WithoutRowid;
      convertToWithoutRowidTable(pParse, p);
    }
  }

  iDb = sqlite3SchemaToIndex(db, p->pSchema);

#ifndef SQLITE_OMIT_CHECK
  /* Resolve names in all CHECK constraint expressions.
  */
................................................................................
){
  Index *pRet = 0;     /* Pointer to return */
  Table *pTab = 0;     /* Table to be indexed */
  Index *pIndex = 0;   /* The index to be created */
  char *zName = 0;     /* Name of the index */
  int nName;           /* Number of characters in zName */
  int i, j;

  DbFixer sFix;        /* For assigning database names to pTable */
  int sortOrderMask;   /* 1 to honor DESC in index.  0 to ignore. */
  sqlite3 *db = pParse->db;
  Db *pDb;             /* The specific table containing the indexed database */
  int iDb;             /* Index of the database that is being written */
  Token *pName = 0;    /* Unqualified name of the index to create */
  struct ExprList_item *pListItem; /* For looping over pList */
................................................................................
#endif

  /* If pList==0, it means this routine was called to make a primary
  ** key out of the last column added to the table under construction.
  ** So create a fake list to simulate this.
  */
  if( pList==0 ){


    pList = sqlite3ExprListAppend(pParse, 0, 0);
    if( pList==0 ) goto exit_create_index;

    pList->a[0].zName = sqlite3DbStrDup(pParse->db,
                                        pTab->aCol[pTab->nCol-1].zName);
    pList->a[0].sortOrder = (u8)sortOrder;
  }

  /* Figure out how many bytes of space are required to store explicitly
  ** specified collation sequence names.
  */
  for(i=0; i<pList->nExpr; i++){

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    corruptSchema(pData, argv[0], 0);
    return 1;
  }

  assert( iDb>=0 && iDb<db->nDb );
  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
  if( argv[1]==0 ){
    corruptSchema(pData, argv[0], 0);
  }else if( argv[2] && argv[2][0] ){
    /* Call the parser to process a CREATE TABLE, INDEX or VIEW.
    ** But because db->init.busy is set to 1, no VDBE code is generated
    ** or executed.  All the parser does is build the internal data
    ** structures that describe the table, index, or view.
    */
    int rc;







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    corruptSchema(pData, argv[0], 0);
    return 1;
  }

  assert( iDb>=0 && iDb<db->nDb );
  if( argv==0 ) return 0;   /* Might happen if EMPTY_RESULT_CALLBACKS are on */
  if( argv[1]==0 ){
    /* NULL root page for a WITHOUT ROWID table */
  }else if( argv[2] && argv[2][0] ){
    /* Call the parser to process a CREATE TABLE, INDEX or VIEW.
    ** But because db->init.busy is set to 1, no VDBE code is generated
    ** or executed.  All the parser does is build the internal data
    ** structures that describe the table, index, or view.
    */
    int rc;

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  LogEst szIdxRow;         /* Estimated average row size in bytes */
  u16 nKeyCol;             /* Number of columns forming the key */
  u16 nColumn;             /* Number of columns stored in the index */
  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */

#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int nSample;             /* Number of elements in aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};
................................................................................
  u8 disableTriggers;  /* True to disable triggers */

  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;                 /* Number of '?' variables seen in the SQL so far */
  int nzVar;                /* Number of available slots in azVar[] */


  u8 explain;               /* True if the EXPLAIN flag is found on the query */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;            /* Number of virtual tables to lock */
#endif
  int nAlias;               /* Number of aliased result set columns */
  int nHeight;              /* Expression tree height of current sub-select */







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  LogEst szIdxRow;         /* Estimated average row size in bytes */
  u16 nKeyCol;             /* Number of columns forming the key */
  u16 nColumn;             /* Number of columns stored in the index */
  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
  unsigned isResized:1;    /* True if resizeIndexObject() has been called */
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  int nSample;             /* Number of elements in aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
#endif
};
................................................................................
  u8 disableTriggers;  /* True to disable triggers */

  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;                 /* Number of '?' variables seen in the SQL so far */
  int nzVar;                /* Number of available slots in azVar[] */
  u8 addrCrTab;             /* Address of OP_CreateTable opcode */
  u8 iPkSortOrder;          /* ASC or DESC for INTEGER PRIMARY KEY */
  u8 explain;               /* True if the EXPLAIN flag is found on the query */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  u8 declareVtab;           /* True if inside sqlite3_declare_vtab() */
  int nVtabLock;            /* Number of virtual tables to lock */
#endif
  int nAlias;               /* Number of aliased result set columns */
  int nHeight;              /* Expression tree height of current sub-select */