build.c

调用sqlite开源数据的小程序

      zStmt[k++] = ' ';
      strcpy(&zStmt[k], z);
      k += strlen(z);
    }
  }
  strcpy(&zStmt[k], zEnd);
  return zStmt;
}

/*
** 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
** occurred.
**
** An entry for the table is made in the master table on disk, unless
** this is a temporary table or db->init.busy==1.  When db->init.busy==1
** it means we are reading the sqlite_master table because we just
** connected to the database or because the sqlite_master table has
** recently changed, so the entry for this table already exists in
** the sqlite_master table.  We do not want to create it again.
**
** If the pSelect argument is not NULL, it means that this routine
** was called to create a table generated from a 
** "CREATE TABLE ... AS SELECT ..." statement.  The column names of
** the new table will match the result set of the SELECT.
*/
void sqlite3EndTable(
  Parse *pParse,          /* Parse context */
  Token *pCons,           /* The ',' token after the last column defn. */
  Token *pEnd,            /* The final ')' token in the CREATE TABLE */
  Select *pSelect         /* Select from a "CREATE ... AS SELECT" */
){
  Table *p;
  sqlite3 *db = pParse->db;

  if( (pEnd==0 && pSelect==0) || pParse->nErr || sqlite3_malloc_failed ) return;
  p = pParse->pNewTable;
  if( p==0 ) return;

  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;
  }

  /* If not initializing, then create a record for the new table
  ** in the SQLITE_MASTER table of the database.  The record number
  ** for the new table entry should already be on the stack.
  **
  ** If this is a TEMPORARY table, write the entry into the auxiliary
  ** file instead of into the main database file.
  */
  if( !db->init.busy ){
    int n;
    Vdbe *v;
    char *zType;    /* "view" or "table" */
    char *zType2;   /* "VIEW" or "TABLE" */
    char *zStmt;    /* Text of the CREATE TABLE or CREATE VIEW statement */

    v = sqlite3GetVdbe(pParse);
    if( v==0 ) return;

    sqlite3VdbeAddOp(v, OP_Close, 0, 0);

    /* Create the rootpage for the new table and push it onto the stack.
    ** A view has no rootpage, so just push a zero onto the stack for
    ** views.  Initialize zType at the same time.
    */
    if( p->pSelect==0 ){
      /* A regular table */
      zType = "table";
      zType2 = "TABLE";
#ifndef SQLITE_OMIT_VIEW
    }else{
      /* A view */
      zType = "view";
      zType2 = "VIEW";
#endif
    }

    /* If this is a CREATE TABLE xx AS SELECT ..., execute the SELECT
    ** statement to populate the new table. The root-page number for the
    ** new table is on the top of the vdbe stack.
    **
    ** Once the SELECT has been coded by sqlite3Select(), it is in a
    ** suitable state to query for the column names and types to be used
    ** by the new table.
    */
    if( pSelect ){
      Table *pSelTab;
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3VdbeAddOp(v, OP_Integer, p->iDb, 0);
      sqlite3VdbeAddOp(v, OP_OpenWrite, 1, 0);
      pParse->nTab = 2;
      sqlite3Select(pParse, pSelect, SRT_Table, 1, 0, 0, 0, 0);
      sqlite3VdbeAddOp(v, OP_Close, 1, 0);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
        if( pSelTab==0 ) return;
        assert( p->aCol==0 );
        p->nCol = pSelTab->nCol;
        p->aCol = pSelTab->aCol;
        pSelTab->nCol = 0;
        pSelTab->aCol = 0;
        sqlite3DeleteTable(0, pSelTab);
      }
    }

    /* Compute the complete text of the CREATE statement */
    if( pSelect ){
      zStmt = createTableStmt(p);
    }else{
      n = pEnd->z - pParse->sNameToken.z + 1;
      zStmt = sqlite3MPrintf("CREATE %s %.*s", zType2, n, pParse->sNameToken.z);
    }

    /* A slot for the record has already been allocated in the 
    ** SQLITE_MASTER table.  We just need to update that slot with all
    ** the information we've collected.  The rowid for the preallocated
    ** slot is the 2nd item on the stack.  The top of the stack is the
    ** root page for the new table (or a 0 if this is a view).
    */
    sqlite3NestedParse(pParse,
      "UPDATE %Q.%s "
         "SET type='%s', name=%Q, tbl_name=%Q, rootpage=#0, sql=%Q "
       "WHERE rowid=#1",
      db->aDb[p->iDb].zName, SCHEMA_TABLE(p->iDb),
      zType,
      p->zName,
      p->zName,
      zStmt
    );
    sqliteFree(zStmt);
    sqlite3ChangeCookie(db, v, p->iDb);

#ifndef SQLITE_OMIT_AUTOINCREMENT
    /* Check to see if we need to create an sqlite_sequence table for
    ** keeping track of autoincrement keys.
    */
    if( p->autoInc ){
      Db *pDb = &db->aDb[p->iDb];
      if( pDb->pSeqTab==0 ){
        sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.sqlite_sequence(name,seq)",
          pDb->zName
        );
      }
    }
#endif

    /* Reparse everything to update our internal data structures */
    sqlite3VdbeOp3(v, OP_ParseSchema, p->iDb, 0,
        sqlite3MPrintf("tbl_name='%q'",p->zName), P3_DYNAMIC);
  }


  /* Add the table to the in-memory representation of the database.
  */
  if( db->init.busy && pParse->nErr==0 ){
    Table *pOld;
    FKey *pFKey; 
    Db *pDb = &db->aDb[p->iDb];
    pOld = sqlite3HashInsert(&pDb->tblHash, p->zName, strlen(p->zName)+1, p);
    if( pOld ){
      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
      return;
    }
#ifndef SQLITE_OMIT_FOREIGN_KEY
    for(pFKey=p->pFKey; pFKey; pFKey=pFKey->pNextFrom){
      int nTo = strlen(pFKey->zTo) + 1;
      pFKey->pNextTo = sqlite3HashFind(&pDb->aFKey, pFKey->zTo, nTo);
      sqlite3HashInsert(&pDb->aFKey, pFKey->zTo, nTo, pFKey);
    }
#endif
    pParse->pNewTable = 0;
    db->nTable++;
    db->flags |= SQLITE_InternChanges;

#ifndef SQLITE_OMIT_ALTERTABLE
    if( !p->pSelect ){
      assert( !pSelect && pCons && pEnd );
      if( pCons->z==0 ) pCons = pEnd;
      p->addColOffset = 13 + (pCons->z - pParse->sNameToken.z);
    }
#endif
  }
}

#ifndef SQLITE_OMIT_VIEW
/*
** The parser calls this routine in order to create a new VIEW
*/
void sqlite3CreateView(
  Parse *pParse,     /* The parsing context */
  Token *pBegin,     /* The CREATE token that begins the statement */
  Token *pName1,     /* The token that holds the name of the view */
  Token *pName2,     /* The token that holds the name of the view */
  Select *pSelect,   /* A SELECT statement that will become the new view */
  int isTemp         /* TRUE for a TEMPORARY view */
){
  Table *p;
  int n;
  const unsigned char *z;
  Token sEnd;
  DbFixer sFix;
  Token *pName;

  if( pParse->nVar>0 ){
    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3StartTable(pParse, pBegin, pName1, pName2, isTemp, 1);
  p = pParse->pNewTable;
  if( p==0 || pParse->nErr ){
    sqlite3SelectDelete(pSelect);
    return;
  }
  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  if( sqlite3FixInit(&sFix, pParse, p->iDb, "view", pName)
    && sqlite3FixSelect(&sFix, pSelect)
  ){
    sqlite3SelectDelete(pSelect);
    return;
  }

  /* Make a copy of the entire SELECT statement that defines the view.
  ** This will force all the Expr.token.z values to be dynamically
  ** allocated rather than point to the input string - which means that
  ** they will persist after the current sqlite3_exec() call returns.
  */
  p->pSelect = sqlite3SelectDup(pSelect);
  sqlite3SelectDelete(pSelect);
  if( !pParse->db->init.busy ){
    sqlite3ViewGetColumnNames(pParse, p);
  }

  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
  ** the end.
  */
  sEnd = pParse->sLastToken;
  if( sEnd.z[0]!=0 && sEnd.z[0]!=';' ){
    sEnd.z += sEnd.n;
  }
  sEnd.n = 0;
  n = sEnd.z - pBegin->z;
  z = (const unsigned char*)pBegin->z;
  while( n>0 && (z[n-1]==';' || isspace(z[n-1])) ){ n--; }
  sEnd.z = &z[n-1];
  sEnd.n = 1;

  /* Use sqlite3EndTable() to add the view to the SQLITE_MASTER table */
  sqlite3EndTable(pParse, 0, &sEnd, 0);
  return;
}
#endif /* SQLITE_OMIT_VIEW */

#ifndef SQLITE_OMIT_VIEW
/*
** The Table structure pTable is really a VIEW.  Fill in the names of
** the columns of the view in the pTable structure.  Return the number
** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
*/
int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
  Table *pSelTab;   /* A fake table from which we get the result set */
  Select *pSel;     /* Copy of the SELECT that implements the view */
  int nErr = 0;     /* Number of errors encountered */
  int n;            /* Temporarily holds the number of cursors assigned */

  assert( pTable );

  /* A positive nCol means the columns names for this view are
  ** already known.
  */
  if( pTable->nCol>0 ) return 0;

  /* A negative nCol is a special marker meaning that we are currently
  ** trying to compute the column names.  If we enter this routine with
  ** a negative nCol, it means two or more views form a loop, like this:
  **
  **     CREATE VIEW one AS SELECT * FROM two;
  **     CREATE VIEW two AS SELECT * FROM one;
  **
  ** Actually, this error is caught previously and so the following test
  ** should always fail.  But we will leave it in place just to be safe.
  */
#if 0
  if( pTable->nCol<0 ){
    sqlite3ErrorMsg(pParse, "view %s is circularly defined", pTable->zName);
    return 1;
  }
#endif
  assert( pTable->nCol>=0 );

  /* If we get this far, it means we need to compute the table names.
  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
  ** "*" elements in the results set of the view and will assign cursors
  ** to the elements of the FROM clause.  But we do not want these changes
  ** to be permanent.  So the computation is done on a copy of the SELECT
  ** statement that defines the view.
  */
  assert( pTable->pSelect );
  pSel = sqlite3SelectDup(pTable->pSelect);
  n = pParse->nTab;
  sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
  pTable->nCol = -1;
  pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
  pParse->nTab = n;
  if( pSelTab ){
    assert( pTable->aCol==0 );
    pTable->nCol = pSelTab->nCol;
    pTable->aCol = pSelTab->aCol;
    pSelTab->nCol = 0;
    pSelTab->aCol = 0;
    sqlite3DeleteTable(0, pSelTab);
    DbSetProperty(pParse->db, pTable->iDb, DB_UnresetViews);
  }else{
    pTable->nCol = 0;
    nErr++;
  }
  sqlite3SelectDelete(pSel);
  return nErr;  
}
#endif /* SQLITE_OMIT_VIEW */

#ifndef SQLITE_OMIT_VIEW
/*
** Clear the column names from every VIEW in database idx.
*/
static void sqliteViewResetAll(sqlite3 *db, int idx){
  HashElem *i;
  if( !DbHasProperty(db, idx, DB_UnresetViews) ) return;
  for(i=sqliteHashFirst(&db->aDb[idx].tblHash); i; i=sqliteHashNext(i)){
    Table *pTab = sqliteHashData(i);
    if( pTab->pSelect ){
      sqliteResetColumnNames(pTab);
    }
  }
  DbClearProperty(db, idx, DB_UnresetViews);
}
#else
# define sqliteViewResetAll(A,B)
#endif /* SQLITE_OMIT_VIEW */

/*
** This function is called by the VDBE to adjust the internal schema
** used by SQLite when the btree layer moves a table root page. The
** root-page of a table or index in database iDb has changed from iFrom
** to iTo.
*/
#ifndef SQLITE_OMIT_AUTOVACUUM
void sqlite3RootPageMoved(Db *pDb, int iFrom, int iTo){
  HashElem *pElem;
  
  for(pElem=sqliteHashFirst(&pDb->tblHash); pElem; pElem=sqliteHashNext(pElem)){
    Table *pTab = sqliteHashData(pElem);
    if( pTab->tnum==iFrom ){
      pTab->tnum = iTo;
      return;
    }
  }
  for(pElem=sqliteHashFirst(&pDb->idxHash); pElem; pElem=sqliteHashNext(pElem)){
    Index *pIdx = sqliteHashData(pElem);
    if( pIdx->tnum==iFrom ){
      pIdx->tnum = iTo;
      return;
    }
  }
  assert(0);
}
#endif

/*
** Write code to erase the table with root-page iTable from database iDb.
** 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);
  sqlite3VdbeAddOp(v, OP_Destroy, iTable, iDb);
#ifndef SQLITE_OMIT_AUTOVACUUM
  /* OP_Destroy pushes an integer onto the stack. 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.
  **
  ** The "#0" in the SQL is a special constant that means whatever value
  ** is on the top of the stack.  See sqlite3RegisterExpr().
  */
  sqlite3NestedParse(pParse, 
     "UPDATE %Q.%s SET rootpage=%d WHERE #0 AND rootpage=#0",
     pParse->db->aDb[iDb].zName, SCHEMA_TABLE(iDb), iTable);
#endif
}

/*
** Write VDBE code to erase table pTab and all associated indices on disk.
** Code to update the sqlite_master tables and internal schema definitions