SQLite

** 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 */
  ExprList *pCNames, /* Optional list of view column names */
  Select *pSelect,   /* A SELECT statement that will become the new view */
  int isTemp,        /* TRUE for a TEMPORARY view */
  int noErr          /* Suppress error messages if VIEW already exists */
){
  Table *p;
  int n;
  const char *z;
  Token sEnd;
  DbFixer sFix;
  Token *pName = 0;
  int iDb;
  sqlite3 *db = pParse->db;

  if( pParse->nVar>0 ){
    sqlite3ErrorMsg(pParse, "parameters are not allowed in views");
    sqlite3SelectDelete(db, pSelect);
    return;
  }
  sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
  sqlite3RestrictColumnListSyntax(pParse, pCNames);
  p = pParse->pNewTable;
  if( p==0 || pParse->nErr ) goto create_view_fail;



  sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  iDb = sqlite3SchemaToIndex(db, p->pSchema);
  sqlite3FixInit(&sFix, pParse, iDb, "view", pName);
  if( sqlite3FixSelect(&sFix, pSelect) ) goto create_view_fail;




  /* 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(db, pSelect, EXPRDUP_REDUCE);
  p->pCheck = sqlite3ExprListDup(db, pCNames, EXPRDUP_REDUCE);
  if( db->mallocFailed ) goto create_view_fail;



  /* Locate the end of the CREATE VIEW statement.  Make sEnd point to
  ** the end.
  */
  sEnd = pParse->sLastToken;
  assert( sEnd.z[0]!=0 );
  if( sEnd.z[0]!=';' ){
    sEnd.z += sEnd.n;
  }
  sEnd.n = 0;
  n = (int)(sEnd.z - pBegin->z);
  assert( n>0 );
  z = pBegin->z;
  while( sqlite3Isspace(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, 0);

create_view_fail:
  sqlite3SelectDelete(db, pSelect);
  sqlite3ExprListDelete(db, pCNames);
  return;
}
#endif /* SQLITE_OMIT_VIEW */

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
/*
** 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 */
  sqlite3 *db = pParse->db;  /* Database connection for malloc errors */
  sqlite3_xauth xAuth;       /* Saved xAuth pointer */
  u8 bEnabledLA;             /* Saved db->lookaside.bEnabled state */

  assert( pTable );

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( sqlite3VtabCallConnect(pParse, pTable) ){
    return SQLITE_ERROR;
  }

  ** 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 );
  bEnabledLA = db->lookaside.bEnabled;
  if( pTable->pCheck ){
    db->lookaside.bEnabled = 0;
    sqlite3ColumnsFromExprList(pParse, pTable->pCheck, 
                               &pTable->nCol, &pTable->aCol);
  }else{
    pSel = sqlite3SelectDup(db, pTable->pSelect, 0);
    if( pSel ){

      n = pParse->nTab;
      sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
      pTable->nCol = -1;
      db->lookaside.bEnabled = 0;
#ifndef SQLITE_OMIT_AUTHORIZATION
      xAuth = db->xAuth;
      db->xAuth = 0;
      pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
      db->xAuth = xAuth;
#else
      pSelTab = sqlite3ResultSetOfSelect(pParse, pSel);
#endif

      pParse->nTab = n;
      if( pSelTab ){
        assert( pTable->aCol==0 );
        pTable->nCol = pSelTab->nCol;
        pTable->aCol = pSelTab->aCol;
        pSelTab->nCol = 0;
        pSelTab->aCol = 0;
        sqlite3DeleteTable(db, pSelTab);
        assert( sqlite3SchemaMutexHeld(db, 0, pTable->pSchema) );

      }else{
        pTable->nCol = 0;
        nErr++;
      }
      sqlite3SelectDelete(db, pSel);
    } else {
      nErr++;
    }
  }
  db->lookaside.bEnabled = bEnabledLA;
  pTable->pSchema->schemaFlags |= DB_UnresetViews;
#endif /* SQLITE_OMIT_VIEW */
  return nErr;  
}
#endif /* !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) */

#ifndef SQLITE_OMIT_VIEW
/*

%type ifexists {int}
ifexists(A) ::= IF EXISTS.   {A = 1;}
ifexists(A) ::= .            {A = 0;}

///////////////////// The CREATE VIEW statement /////////////////////////////
//
%ifndef SQLITE_OMIT_VIEW
cmd ::= createkw(X) temp(T) VIEW ifnotexists(E) nm(Y) dbnm(Z) idxlist_opt(C)
          AS select(S). {
  sqlite3CreateView(pParse, &X, &Y, &Z, C, S, T, E);
}
cmd ::= DROP VIEW ifexists(E) fullname(X). {
  sqlite3DropTable(pParse, X, 1, E);
}
%endif  SQLITE_OMIT_VIEW

//////////////////////// The SELECT statement /////////////////////////////////

setlist(A) ::= nm(X) EQ expr(Y). {
  A = sqlite3ExprListAppend(pParse, 0, Y.pExpr);
  sqlite3ExprListSetName(pParse, A, &X, 1);
}

////////////////////////// The INSERT command /////////////////////////////////
//
cmd ::= with(W) insert_cmd(R) INTO fullname(X) idlist_opt(F) select(S). {
  sqlite3WithPush(pParse, W, 1);
  sqlite3Insert(pParse, X, S, F, R);
}
cmd ::= with(W) insert_cmd(R) INTO fullname(X) idlist_opt(F) DEFAULT VALUES.
{
  sqlite3WithPush(pParse, W, 1);
  sqlite3Insert(pParse, X, 0, F, R);
}

%type insert_cmd {u8}
insert_cmd(A) ::= INSERT orconf(R).   {A = R;}
insert_cmd(A) ::= REPLACE.            {A = OE_Replace;}

%type idlist_opt {IdList*}
%destructor idlist_opt {sqlite3IdListDelete(pParse->db, $$);}
%type idlist {IdList*}
%destructor idlist {sqlite3IdListDelete(pParse->db, $$);}

idlist_opt(A) ::= .                       {A = 0;}
idlist_opt(A) ::= LP idlist(X) RP.    {A = X;}
idlist(A) ::= idlist(X) COMMA nm(Y).
    {A = sqlite3IdListAppend(pParse->db,X,&Y);}
idlist(A) ::= nm(Y).
    {A = sqlite3IdListAppend(pParse->db,0,&Y);}

/////////////////////////// Expression Processing /////////////////////////////
//

%destructor trigger_cmd {sqlite3DeleteTriggerStep(pParse->db, $$);}
// UPDATE 
trigger_cmd(A) ::=
   UPDATE orconf(R) trnm(X) tridxby SET setlist(Y) where_opt(Z).  
   { A = sqlite3TriggerUpdateStep(pParse->db, &X, Y, Z, R); }

// INSERT
trigger_cmd(A) ::= insert_cmd(R) INTO trnm(X) idlist_opt(F) select(S).
               {A = sqlite3TriggerInsertStep(pParse->db, &X, F, S, R);}

// DELETE
trigger_cmd(A) ::= DELETE FROM trnm(X) tridxby where_opt(Y).
               {A = sqlite3TriggerDeleteStep(pParse->db, &X, Y);}

// SELECT

**
** Only the column names are computed.  Column.zType, Column.zColl,
** and other fields of Column are zeroed.
**
** Return SQLITE_OK on success.  If a memory allocation error occurs,
** store NULL in *paCol and 0 in *pnCol and return SQLITE_NOMEM.
*/
int sqlite3ColumnsFromExprList(
  Parse *pParse,          /* Parsing context */
  ExprList *pEList,       /* Expr list from which to derive column names */
  i16 *pnCol,             /* Write the number of columns here */
  Column **paCol          /* Write the new column list here */
){
  sqlite3 *db = pParse->db;   /* Database connection */
  int i, j;                   /* Loop counters */

  }
  /* The sqlite3ResultSetOfSelect() is only used n contexts where lookaside
  ** is disabled */
  assert( db->lookaside.bEnabled==0 );
  pTab->nRef = 1;
  pTab->zName = 0;
  pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) );
  sqlite3ColumnsFromExprList(pParse, pSelect->pEList, &pTab->nCol, &pTab->aCol);
  selectAddColumnTypeAndCollation(pParse, pTab, pSelect);
  pTab->iPKey = -1;
  if( db->mallocFailed ){
    sqlite3DeleteTable(db, pTab);
    return 0;
  }
  return pTab;

        );
        pParse->pWith = pSavedWith;
        return SQLITE_ERROR;
      }
      pEList = pCte->pCols;
    }

    sqlite3ColumnsFromExprList(pParse, pEList, &pTab->nCol, &pTab->aCol);
    if( bMayRecursive ){
      if( pSel->selFlags & SF_Recursive ){
        pCte->zErr = "multiple recursive references: %s";
      }else{
        pCte->zErr = "recursive reference in a subquery: %s";
      }
      sqlite3WalkSelect(pWalker, pSel);

      assert( pFrom->pTab==0 );
      if( sqlite3WalkSelect(pWalker, pSel) ) return WRC_Abort;
      pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
      if( pTab==0 ) return WRC_Abort;
      pTab->nRef = 1;
      pTab->zName = sqlite3MPrintf(db, "sqlite_sq_%p", (void*)pTab);
      while( pSel->pPrior ){ pSel = pSel->pPrior; }
      sqlite3ColumnsFromExprList(pParse, pSel->pEList,&pTab->nCol,&pTab->aCol);
      pTab->iPKey = -1;
      pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) );
      pTab->tabFlags |= TF_Ephemeral;
#endif
    }else{
      /* An ordinary table or view name in the FROM clause */
      assert( pFrom->pTab==0 );

struct Table {
  char *zName;         /* Name of the table or view */
  Column *aCol;        /* Information about each column */
  Index *pIndex;       /* List of SQL indexes on this table. */
  Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
  FKey *pFKey;         /* Linked list of all foreign keys in this table */
  char *zColAff;       /* String defining the affinity of each column */

  ExprList *pCheck;    /* All CHECK constraints */

                       /*   ... also used as column name list in a VIEW */
  int tnum;            /* Root BTree page for this table */
  i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
  i16 nCol;            /* Number of columns in this table */
  u16 nRef;            /* Number of pointers to this Table */
  LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
  LogEst szTabRow;     /* Estimated size of each table row in bytes */
#ifdef SQLITE_ENABLE_COSTMULT

void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
void sqlite3ResetAllSchemasOfConnection(sqlite3*);
void sqlite3ResetOneSchema(sqlite3*,int);
void sqlite3CollapseDatabaseArray(sqlite3*);
void sqlite3BeginParse(Parse*,int);
void sqlite3CommitInternalChanges(sqlite3*);
void sqlite3DeleteColumnNames(sqlite3*,Table*);
int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
Table *sqlite3ResultSetOfSelect(Parse*,Select*);
void sqlite3OpenMasterTable(Parse *, int);
Index *sqlite3PrimaryKeyIndex(Table*);
i16 sqlite3ColumnOfIndex(Index*, i16);
void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
void sqlite3AddColumn(Parse*,Token*);
void sqlite3AddNotNull(Parse*, int);

RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
void sqlite3RowSetClear(RowSet*);
void sqlite3RowSetInsert(RowSet*, i64);
int sqlite3RowSetTest(RowSet*, int iBatch, i64);
int sqlite3RowSetNext(RowSet*, i64*);

void sqlite3CreateView(Parse*,Token*,Token*,Token*,ExprList*,Select*,int,int);

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
  int sqlite3ViewGetColumnNames(Parse*,Table*);
#else
# define sqlite3ViewGetColumnNames(A,B) 0
#endif

} {xyz 2 pqr 7 c-b 1}
do_test view-3.3.2 {
  execsql2 {
    CREATE VIEW v1b AS SELECT t1.a, b+c, t1.c FROM t1;
    SELECT * FROM v1b LIMIT 1
  }
} {a 2 b+c 7 c 4}
do_test view-3.3.3 {
  execsql2 {
    CREATE VIEW v1c(x,y,z) AS SELECT a, b+c, c-b FROM t1;
    SELECT * FROM v1c LIMIT 1;
  }
} {x 2 y 7 z 1}
do_catchsql_test view-3.3.4 {
  CREATE VIEW v1err(x,y DESC,z) AS SELECT a, b+c, c-b FROM t1;
} {1 {syntax error after column name "y"}}

ifcapable compound {
do_test  view-3.4 {
  execsql2 {
    CREATE VIEW v3 AS SELECT a FROM t1 UNION SELECT b FROM t1 ORDER BY b;
    SELECT * FROM v3 LIMIT 4;
  }

  sqlite3 db test.db
  execsql {
    SELECT * FROM v6 ORDER BY xyz;
  }
} {7 2 13 5 19 8 27 12}
do_test view-8.3 {
  execsql {
    CREATE VIEW v7(a) AS SELECT pqr+xyz FROM v6;
    SELECT * FROM v7 ORDER BY a;
  }
} {9 18 27 39}

ifcapable subquery {
  do_test view-8.4 {
    execsql {