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Overview
Comment:Work toward making the schema parsing logic simplier and more compact.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: c52ca2c0662bb30ab34574f933429512655b19ff
User & Date: drh 2016-01-15 15:06:41
Context
2016-01-15
16:11
Remove unnecessary de-initialization of the Parse object. check-in: 75ab30c5 user: drh tags: trunk
15:06
Work toward making the schema parsing logic simplier and more compact. check-in: c52ca2c0 user: drh tags: trunk
05:39
Fix a couple C99-isms in FTS5 that cause compile errors on MSVC. check-in: 584848d4 user: mistachkin tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/btree.c.

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  **
  ** This error is caught long before control reaches this point.
  */
  if( NEVER(pBt->pCursor) ){
    sqlite3ConnectionBlocked(p->db, pBt->pCursor->pBtree->db);
    return SQLITE_LOCKED_SHAREDCACHE;
  }









  rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
  if( rc ) return rc;
  rc = sqlite3BtreeClearTable(p, iTable, 0);
  if( rc ){
    releasePage(pPage);
    return rc;
  }

  *piMoved = 0;

  if( iTable>1 ){
#ifdef SQLITE_OMIT_AUTOVACUUM
    freePage(pPage, &rc);
    releasePage(pPage);
#else
    if( pBt->autoVacuum ){
      Pgno maxRootPgno;
      sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &maxRootPgno);

      if( iTable==maxRootPgno ){
        /* If the table being dropped is the table with the largest root-page
        ** number in the database, put the root page on the free list. 
        */
        freePage(pPage, &rc);
        releasePage(pPage);
        if( rc!=SQLITE_OK ){
          return rc;
        }
      }else{
        /* The table being dropped does not have the largest root-page
        ** number in the database. So move the page that does into the 
        ** gap left by the deleted root-page.
        */
        MemPage *pMove;
        releasePage(pPage);
        rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
        if( rc!=SQLITE_OK ){
          return rc;
        }
        rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable, 0);
        releasePage(pMove);
        if( rc!=SQLITE_OK ){
          return rc;
        }
        pMove = 0;
        rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
        freePage(pMove, &rc);
        releasePage(pMove);
        if( rc!=SQLITE_OK ){
          return rc;
        }
        *piMoved = maxRootPgno;
      }

      /* Set the new 'max-root-page' value in the database header. This
      ** is the old value less one, less one more if that happens to
      ** be a root-page number, less one again if that is the
      ** PENDING_BYTE_PAGE.
      */
      maxRootPgno--;
      while( maxRootPgno==PENDING_BYTE_PAGE(pBt)
             || PTRMAP_ISPAGE(pBt, maxRootPgno) ){
        maxRootPgno--;
      }
      assert( maxRootPgno!=PENDING_BYTE_PAGE(pBt) );

      rc = sqlite3BtreeUpdateMeta(p, 4, maxRootPgno);
    }else{
      freePage(pPage, &rc);
      releasePage(pPage);
    }
#endif
  }else{
    /* If sqlite3BtreeDropTable was called on page 1.
    ** This really never should happen except in a corrupt
    ** database. 
    */
    zeroPage(pPage, PTF_INTKEY|PTF_LEAF );
    releasePage(pPage);
  }
  return rc;  
}
int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
  int rc;
  sqlite3BtreeEnter(p);
  rc = btreeDropTable(p, iTable, piMoved);
  sqlite3BtreeLeave(p);







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  **
  ** This error is caught long before control reaches this point.
  */
  if( NEVER(pBt->pCursor) ){
    sqlite3ConnectionBlocked(p->db, pBt->pCursor->pBtree->db);
    return SQLITE_LOCKED_SHAREDCACHE;
  }

  /*
  ** It is illegal to drop the sqlite_master table on page 1.  But again,
  ** this error is caught long before reaching this point.
  */
  if( NEVER(iTable<2) ){
    return SQLITE_CORRUPT_BKPT;
  }

  rc = btreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
  if( rc ) return rc;
  rc = sqlite3BtreeClearTable(p, iTable, 0);
  if( rc ){
    releasePage(pPage);
    return rc;
  }

  *piMoved = 0;


#ifdef SQLITE_OMIT_AUTOVACUUM
  freePage(pPage, &rc);
  releasePage(pPage);
#else
  if( pBt->autoVacuum ){
    Pgno maxRootPgno;
    sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &maxRootPgno);

    if( iTable==maxRootPgno ){
      /* If the table being dropped is the table with the largest root-page
      ** number in the database, put the root page on the free list. 
      */
      freePage(pPage, &rc);
      releasePage(pPage);
      if( rc!=SQLITE_OK ){
        return rc;
      }
    }else{
      /* The table being dropped does not have the largest root-page
      ** number in the database. So move the page that does into the 
      ** gap left by the deleted root-page.
      */
      MemPage *pMove;
      releasePage(pPage);
      rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
      if( rc!=SQLITE_OK ){
        return rc;
      }
      rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable, 0);
      releasePage(pMove);
      if( rc!=SQLITE_OK ){
        return rc;
      }
      pMove = 0;
      rc = btreeGetPage(pBt, maxRootPgno, &pMove, 0);
      freePage(pMove, &rc);
      releasePage(pMove);
      if( rc!=SQLITE_OK ){
        return rc;
      }
      *piMoved = maxRootPgno;
    }

    /* Set the new 'max-root-page' value in the database header. This
    ** is the old value less one, less one more if that happens to
    ** be a root-page number, less one again if that is the
    ** PENDING_BYTE_PAGE.
    */
    maxRootPgno--;
    while( maxRootPgno==PENDING_BYTE_PAGE(pBt)
           || PTRMAP_ISPAGE(pBt, maxRootPgno) ){
      maxRootPgno--;
    }
    assert( maxRootPgno!=PENDING_BYTE_PAGE(pBt) );

    rc = sqlite3BtreeUpdateMeta(p, 4, maxRootPgno);
  }else{
    freePage(pPage, &rc);
    releasePage(pPage);
  }
#endif








  return rc;  
}
int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
  int rc;
  sqlite3BtreeEnter(p);
  rc = btreeDropTable(p, iTable, piMoved);
  sqlite3BtreeLeave(p);

Changes to src/build.c.

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  Token *pName1,      /* The "xxx" in the name "xxx.yyy" or "xxx" */
  Token *pName2,      /* The "yyy" in the name "xxx.yyy" */
  Token **pUnqual     /* Write the unqualified object name here */
){
  int iDb;                    /* Database holding the object */
  sqlite3 *db = pParse->db;


  if( ALWAYS(pName2!=0) && pName2->n>0 ){
    if( db->init.busy ) {
      sqlite3ErrorMsg(pParse, "corrupt database");
      return -1;
    }
    *pUnqual = pName2;
    iDb = sqlite3FindDb(db, pName1);
    if( iDb<0 ){
................................................................................
  Table *pTable;
  char *zName = 0; /* The name of the new table */
  sqlite3 *db = pParse->db;
  Vdbe *v;
  int iDb;         /* Database number to create the table in */
  Token *pName;    /* Unqualified name of the table to create */

  /* The table or view name to create is passed to this routine via tokens
  ** pName1 and pName2. If the table name was fully qualified, for example:
  **

  ** CREATE TABLE xxx.yyy (...);
  ** 

  ** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
  ** the table name is not fully qualified, i.e.:
  **
  ** CREATE TABLE yyy(...);
  **
  ** Then pName1 is set to "yyy" and pName2 is "".
  **
  ** The call below sets the pName pointer to point at the token (pName1 or
  ** pName2) that stores the unqualified table name. The variable iDb is
  ** set to the index of the database that the table or view is to be
  ** created in.
  */
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  if( iDb<0 ) return;
  if( !OMIT_TEMPDB && isTemp && pName2->n>0 && iDb!=1 ){
    /* If creating a temp table, the name may not be qualified. Unless 
    ** the database name is "temp" anyway.  */
    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
    return;
  }
  if( !OMIT_TEMPDB && isTemp ) iDb = 1;


  pParse->sNameToken = *pName;
  zName = sqlite3NameFromToken(db, pName);
  if( zName==0 ) return;
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto begin_table_error;
  }
  if( db->init.iDb==1 ) isTemp = 1;
#ifndef SQLITE_OMIT_AUTHORIZATION
  assert( (isTemp & 1)==isTemp );


  {
    int code;






    char *zDb = db->aDb[iDb].zName;
    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(isTemp), 0, zDb) ){
      goto begin_table_error;
    }
    if( isView ){
      if( !OMIT_TEMPDB && isTemp ){
        code = SQLITE_CREATE_TEMP_VIEW;
      }else{
        code = SQLITE_CREATE_VIEW;
      }
    }else{
      if( !OMIT_TEMPDB && isTemp ){
        code = SQLITE_CREATE_TEMP_TABLE;
      }else{
        code = SQLITE_CREATE_TABLE;
      }
    }
    if( !isVirtual && sqlite3AuthCheck(pParse, code, zName, 0, zDb) ){

      goto begin_table_error;
    }
  }
#endif

  /* Make sure the new table name does not collide with an existing
  ** index or table name in the same database.  Issue an error message if
................................................................................
  assert( !db->init.busy || !pSelect );

  /* If the db->init.busy is 1 it means we are reading the SQL off the
  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
  ** So do not write to the disk again.  Extract the root page number
  ** for the table from the db->init.newTnum field.  (The page number
  ** should have been put there by the sqliteOpenCb routine.)



  */
  if( db->init.busy ){
    p->tnum = db->init.newTnum;

  }

  /* Special processing for WITHOUT ROWID Tables */
  if( tabOpts & TF_WithoutRowid ){
    if( (p->tabFlags & TF_Autoincrement) ){
      sqlite3ErrorMsg(pParse,
          "AUTOINCREMENT not allowed on WITHOUT ROWID tables");
................................................................................
** Also write code to modify the sqlite_master table and internal schema
** if a root-page of another table is moved by the btree-layer whilst
** erasing iTable (this can happen with an auto-vacuum database).
*/ 
static void destroyRootPage(Parse *pParse, int iTable, int iDb){
  Vdbe *v = sqlite3GetVdbe(pParse);
  int r1 = sqlite3GetTempReg(pParse);

  sqlite3VdbeAddOp3(v, OP_Destroy, iTable, r1, iDb);
  sqlite3MayAbort(pParse);
#ifndef SQLITE_OMIT_AUTOVACUUM
  /* OP_Destroy stores an in integer r1. If this integer
  ** is non-zero, then it is the root page number of a table moved to
  ** location iTable. The following code modifies the sqlite_master table to
  ** reflect this.







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  Token *pName1,      /* The "xxx" in the name "xxx.yyy" or "xxx" */
  Token *pName2,      /* The "yyy" in the name "xxx.yyy" */
  Token **pUnqual     /* Write the unqualified object name here */
){
  int iDb;                    /* Database holding the object */
  sqlite3 *db = pParse->db;

  assert( pName2!=0 );
  if( pName2->n>0 ){
    if( db->init.busy ) {
      sqlite3ErrorMsg(pParse, "corrupt database");
      return -1;
    }
    *pUnqual = pName2;
    iDb = sqlite3FindDb(db, pName1);
    if( iDb<0 ){
................................................................................
  Table *pTable;
  char *zName = 0; /* The name of the new table */
  sqlite3 *db = pParse->db;
  Vdbe *v;
  int iDb;         /* Database number to create the table in */
  Token *pName;    /* Unqualified name of the table to create */

  if( db->init.busy && db->init.newTnum==1 ){
    /* Special case:  Parsing the sqlite_master or sqlite_temp_master schema */

    iDb = db->init.iDb;
    zName = sqlite3DbStrDup(db, SCHEMA_TABLE(iDb));

    pName = pName1;
  }else{
    /* The common case */










    iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
    if( iDb<0 ) return;
    if( !OMIT_TEMPDB && isTemp && pName2->n>0 && iDb!=1 ){
      /* If creating a temp table, the name may not be qualified. Unless 
      ** the database name is "temp" anyway.  */
      sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
      return;
    }
    if( !OMIT_TEMPDB && isTemp ) iDb = 1;
    zName = sqlite3NameFromToken(db, pName);
  }
  pParse->sNameToken = *pName;

  if( zName==0 ) return;
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto begin_table_error;
  }
  if( db->init.iDb==1 ) isTemp = 1;
#ifndef SQLITE_OMIT_AUTHORIZATION

  assert( isTemp==0 || isTemp==1 );
  assert( isView==0 || isView==1 );
  {

    static const u8 aCode[] = {
       SQLITE_CREATE_TABLE,
       SQLITE_CREATE_TEMP_TABLE,
       SQLITE_CREATE_VIEW,
       SQLITE_CREATE_TEMP_VIEW
    };
    char *zDb = db->aDb[iDb].zName;
    if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(isTemp), 0, zDb) ){
      goto begin_table_error;
    }













    if( !isVirtual && sqlite3AuthCheck(pParse, (int)aCode[isTemp+2*isView],
                                       zName, 0, zDb) ){
      goto begin_table_error;
    }
  }
#endif

  /* Make sure the new table name does not collide with an existing
  ** index or table name in the same database.  Issue an error message if
................................................................................
  assert( !db->init.busy || !pSelect );

  /* If the db->init.busy is 1 it means we are reading the SQL off the
  ** "sqlite_master" or "sqlite_temp_master" table on the disk.
  ** So do not write to the disk again.  Extract the root page number
  ** for the table from the db->init.newTnum field.  (The page number
  ** should have been put there by the sqliteOpenCb routine.)
  **
  ** If the root page number is 1, that means this is the sqlite_master
  ** table itself.  So mark it read-only.
  */
  if( db->init.busy ){
    p->tnum = db->init.newTnum;
    if( p->tnum==1 ) p->tabFlags |= TF_Readonly;
  }

  /* Special processing for WITHOUT ROWID Tables */
  if( tabOpts & TF_WithoutRowid ){
    if( (p->tabFlags & TF_Autoincrement) ){
      sqlite3ErrorMsg(pParse,
          "AUTOINCREMENT not allowed on WITHOUT ROWID tables");
................................................................................
** Also write code to modify the sqlite_master table and internal schema
** if a root-page of another table is moved by the btree-layer whilst
** erasing iTable (this can happen with an auto-vacuum database).
*/ 
static void destroyRootPage(Parse *pParse, int iTable, int iDb){
  Vdbe *v = sqlite3GetVdbe(pParse);
  int r1 = sqlite3GetTempReg(pParse);
  assert( iTable>1 );
  sqlite3VdbeAddOp3(v, OP_Destroy, iTable, r1, iDb);
  sqlite3MayAbort(pParse);
#ifndef SQLITE_OMIT_AUTOVACUUM
  /* OP_Destroy stores an in integer r1. If this integer
  ** is non-zero, then it is the root page number of a table moved to
  ** location iTable. The following code modifies the sqlite_master table to
  ** reflect this.

Changes to src/prepare.c.

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*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  int i;
#ifndef SQLITE_OMIT_DEPRECATED
  int size;
#endif
  Table *pTab;
  Db *pDb;
  char const *azArg[4];
  int meta[5];
  InitData initData;
  char const *zMasterSchema;
  char const *zMasterName;
  int openedTransaction = 0;

  /*
  ** The master database table has a structure like this
  */
  static const char master_schema[] = 
     "CREATE TABLE sqlite_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#ifndef SQLITE_OMIT_TEMPDB
  static const char temp_master_schema[] = 
     "CREATE TEMP TABLE sqlite_temp_master(\n"
     "  type text,\n"
     "  name text,\n"
     "  tbl_name text,\n"
     "  rootpage integer,\n"
     "  sql text\n"
     ")"
  ;
#else
  #define temp_master_schema 0
#endif

  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pSchema );
  assert( sqlite3_mutex_held(db->mutex) );
  assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );

  /* zMasterSchema and zInitScript are set to point at the master schema
  ** and initialisation script appropriate for the database being
  ** initialized. zMasterName is the name of the master table.
  */
  if( !OMIT_TEMPDB && iDb==1 ){
    zMasterSchema = temp_master_schema;
  }else{
    zMasterSchema = master_schema;
  }
  zMasterName = SCHEMA_TABLE(iDb);





  /* Construct the schema tables.  */
  azArg[0] = zMasterName;
  azArg[1] = "1";
  azArg[2] = zMasterSchema;


  azArg[3] = 0;
  initData.db = db;
  initData.iDb = iDb;
  initData.rc = SQLITE_OK;
  initData.pzErrMsg = pzErrMsg;
  sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
  if( initData.rc ){
    rc = initData.rc;
    goto error_out;
  }
  pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
  if( ALWAYS(pTab) ){
    pTab->tabFlags |= TF_Readonly;
  }

  /* Create a cursor to hold the database open
  */
  pDb = &db->aDb[iDb];
  if( pDb->pBt==0 ){
    if( !OMIT_TEMPDB && ALWAYS(iDb==1) ){
      DbSetProperty(db, 1, DB_SchemaLoaded);
................................................................................

  /* Read the schema information out of the schema tables
  */
  assert( db->init.busy );
  {
    char *zSql;
    zSql = sqlite3MPrintf(db, 
        "SELECT name, rootpage, sql FROM '%q'.%s ORDER BY rowid",
        db->aDb[iDb].zName, zMasterName);
#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      sqlite3_xauth xAuth;
      xAuth = db->xAuth;
      db->xAuth = 0;
#endif







<




<
|


<
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<
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<
<
<
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<





<
<
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>
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>
|
|

<
>
>










<
<
<
<







 







|







133
134
135
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139

140
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143

144
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146


























147
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151











152
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158

159
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171
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177
...
282
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*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  int i;
#ifndef SQLITE_OMIT_DEPRECATED
  int size;
#endif

  Db *pDb;
  char const *azArg[4];
  int meta[5];
  InitData initData;

  const char *zMasterName;
  int openedTransaction = 0;



























  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pSchema );
  assert( sqlite3_mutex_held(db->mutex) );
  assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );












  /* Construct the in-memory representation schema tables (sqlite_master or
  ** sqlite_temp_master) by invoking the parser directly.  The appropriate
  ** table name will be inserted automatically by the parser so we can just
  ** use the abbreviation "x" here.  The parser will also automatically tag
  ** the schema table as read-only. */
  azArg[0] = zMasterName = SCHEMA_TABLE(iDb);
  azArg[1] = "1";

  azArg[2] = "CREATE TABLE x(type text,name text,tbl_name text,"
                            "rootpage integer,sql text)";
  azArg[3] = 0;
  initData.db = db;
  initData.iDb = iDb;
  initData.rc = SQLITE_OK;
  initData.pzErrMsg = pzErrMsg;
  sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
  if( initData.rc ){
    rc = initData.rc;
    goto error_out;
  }





  /* Create a cursor to hold the database open
  */
  pDb = &db->aDb[iDb];
  if( pDb->pBt==0 ){
    if( !OMIT_TEMPDB && ALWAYS(iDb==1) ){
      DbSetProperty(db, 1, DB_SchemaLoaded);
................................................................................

  /* Read the schema information out of the schema tables
  */
  assert( db->init.busy );
  {
    char *zSql;
    zSql = sqlite3MPrintf(db, 
        "SELECT name, rootpage, sql FROM \"%w\".%s ORDER BY rowid",
        db->aDb[iDb].zName, zMasterName);
#ifndef SQLITE_OMIT_AUTHORIZATION
    {
      sqlite3_xauth xAuth;
      xAuth = db->xAuth;
      db->xAuth = 0;
#endif

Changes to src/vdbe.c.

5095
5096
5097
5098
5099
5100
5101

5102
5103
5104
5105
5106
5107
5108
** See also: Clear
*/
case OP_Destroy: {     /* out2 */
  int iMoved;
  int iDb;

  assert( p->readOnly==0 );

  pOut = out2Prerelease(p, pOp);
  pOut->flags = MEM_Null;
  if( db->nVdbeRead > db->nVDestroy+1 ){
    rc = SQLITE_LOCKED;
    p->errorAction = OE_Abort;
  }else{
    iDb = pOp->p3;







>







5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
** See also: Clear
*/
case OP_Destroy: {     /* out2 */
  int iMoved;
  int iDb;

  assert( p->readOnly==0 );
  assert( pOp->p1>1 );
  pOut = out2Prerelease(p, pOp);
  pOut->flags = MEM_Null;
  if( db->nVdbeRead > db->nVDestroy+1 ){
    rc = SQLITE_LOCKED;
    p->errorAction = OE_Abort;
  }else{
    iDb = pOp->p3;