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Overview
Comment:Minor code and comment cleanup. (CVS 2165)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: d012628a78edaa8d3cb438a7dcc3770b2eb8588b
User & Date: drh 2004-12-14 03:34:34
Context
2004-12-16
21:09
Make sure LIMITs are handled correctly on UNION operators. Ticket #1035. (CVS 2166) check-in: ece0085f user: drh tags: trunk
2004-12-14
03:34
Minor code and comment cleanup. (CVS 2165) check-in: d012628a user: drh tags: trunk
2004-12-10
18:00
Factor the test for zName==NULL out of the loop. Ticket #1032. (CVS 2164) check-in: 7f38f67c user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/build.c.

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**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.289 2004/12/07 12:29:18 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Check to see if the schema for the database needs
** to be read from the SQLITE_MASTER and SQLITE_TEMP_MASTER tables.
** If it does, then read it.
*/
void sqlite3BeginParse(Parse *pParse, int explainFlag){
  pParse->explain = explainFlag;
  pParse->nVar = 0;
}

/*
................................................................................
      sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->cookieGoto);
    }

    /* Add a No-op that contains the complete text of the compiled SQL
    ** statement as its P3 argument.  This does not change the functionality
    ** of the program. 
    **
    ** This is used to implement sqlite3_trace() functionality.
    */
    sqlite3VdbeOp3(v, OP_Noop, 0, 0, pParse->zSql, pParse->zTail-pParse->zSql);
  }


  /* Get the VDBE program ready for execution
  */
................................................................................

/*
** The token *pName contains the name of a database (either "main" or
** "temp" or the name of an attached db). This routine returns the
** index of the named database in db->aDb[], or -1 if the named db 
** does not exist.
*/
int findDb(sqlite3 *db, Token *pName){
  int i;         /* Database number */
  int n;         /* Number of characters in the name */
  Db *pDb;       /* A database whose name space is being searched */
  char *zName;   /* Name we are searching for */

  zName = sqlite3NameFromToken(pName);
  if( zName ){
................................................................................
  Token *pName1,   /* First part of the name of the table or view */
  Token *pName2,   /* Second part of the name of the table or view */
  int isTemp,      /* True if this is a TEMP table */
  int isView       /* True if this is a VIEW */
){
  Table *pTable;
  Index *pIdx;
  char *zName;
  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:
................................................................................
  ** created in.
  */
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  if( iDb<0 ) return;
  if( isTemp && iDb>1 ){
    /* If creating a temp table, the name may not be qualified */
    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");
    pParse->nErr++;
    return;
  }
  if( isTemp ) iDb = 1;

  pParse->sNameToken = *pName;
  zName = sqlite3NameFromToken(pName);
  if( zName==0 ) return;
  if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    sqliteFree(zName);
    return;
  }
  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) ){
      sqliteFree(zName);
      return;
    }
    if( isView ){
      if( isTemp ){
        code = SQLITE_CREATE_TEMP_VIEW;
      }else{
        code = SQLITE_CREATE_VIEW;
      }
................................................................................
      if( isTemp ){
        code = SQLITE_CREATE_TEMP_TABLE;
      }else{
        code = SQLITE_CREATE_TABLE;
      }
    }
    if( sqlite3AuthCheck(pParse, code, zName, 0, zDb) ){
      sqliteFree(zName);
      return;
    }
  }
#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
  ** it does.
  */
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) return;
  pTable = sqlite3FindTable(db, zName, db->aDb[iDb].zName);
  if( pTable ){
    sqlite3ErrorMsg(pParse, "table %T already exists", pName);
    sqliteFree(zName);
    return;
  }
  if( (pIdx = sqlite3FindIndex(db, zName, 0))!=0 && 
      ( iDb==0 || !db->init.busy) ){
    sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
    sqliteFree(zName);
    return;
  }
  pTable = sqliteMalloc( sizeof(Table) );
  if( pTable==0 ){
    pParse->rc = SQLITE_NOMEM;
    pParse->nErr++;
    sqliteFree(zName);
    return;
  }
  pTable->zName = zName;
  pTable->nCol = 0;
  pTable->aCol = 0;
  pTable->iPKey = -1;
  pTable->pIndex = 0;
  pTable->iDb = iDb;
................................................................................
    sqlite3OpenMasterTable(v, iDb);
    sqlite3VdbeAddOp(v, OP_NewRecno, 0, 0);
    sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
    sqlite3VdbeAddOp(v, OP_String8, 0, 0);
    sqlite3VdbeAddOp(v, OP_PutIntKey, 0, 0);
    sqlite3VdbeAddOp(v, OP_Close, 0, 0);
  }








}

/*
** Add a new column to the table currently being constructed.
**
** The parser calls this routine once for each column declaration
** in a CREATE TABLE statement.  sqlite3StartTable() gets called
................................................................................
** most recently added column of the table is the primary key.
**
** A table can have at most one primary key.  If the table already has
** a primary key (and this is the second primary key) then create an
** error.
**
** If the PRIMARY KEY is on a single column whose datatype is INTEGER,
** then we will try to use that column as the row id.  (Exception:
** For backwards compatibility with older databases, do not do this
** if the file format version number is less than 1.)  Set the Table.iPKey
** field of the table under construction to be the index of the
** INTEGER PRIMARY KEY column.  Table.iPKey is set to -1 if there is
** no INTEGER PRIMARY KEY.
**
** If the key is not an INTEGER PRIMARY KEY, then create a unique
** index for the key.  No index is created for INTEGER PRIMARY KEYs.
*/
................................................................................
  sqlite3VdbeAddOp(v, OP_Next, iTab, addr1+1);
  sqlite3VdbeChangeP2(v, addr1, sqlite3VdbeCurrentAddr(v));
  sqlite3VdbeAddOp(v, OP_Close, iTab, 0);
  sqlite3VdbeAddOp(v, OP_Close, iIdx, 0);
}

/*
** Create a new index for an SQL table.  pIndex is the name of the index 
** and pTable is the name of the table that is to be indexed.  Both will 
** be NULL for a primary key or an index that is created to satisfy a
** UNIQUE constraint.  If pTable and pIndex are NULL, use pParse->pNewTable
** as the table to be indexed.  pParse->pNewTable is a table that is
** currently being constructed by a CREATE TABLE statement.
**
** pList is a list of columns to be indexed.  pList will be NULL if this
** is a primary key or unique-constraint on the most recent column added
** to the table currently under construction.  
*/
void sqlite3CreateIndex(
  Parse *pParse,   /* All information about this parse */
  Token *pName1,   /* First part of index name. May be NULL */
  Token *pName2,   /* Second part of index name. May be NULL */
  SrcList *pTblName,  /* Table to index. Use pParse->pNewTable if 0 */
  ExprList *pList,   /* A list of columns to be indexed */
  int onError,     /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  Token *pStart,   /* The CREATE token that begins a CREATE TABLE statement */
  Token *pEnd      /* The ")" that closes the CREATE INDEX statement */
){
  Table *pTab = 0; /* Table to be indexed */
  Index *pIndex = 0; /* The index to be created */
  char *zName = 0;
  int i, j;
  Token nullId;    /* Fake token for an empty ID list */
  DbFixer sFix;    /* For assigning database names to pTable */
  int isTemp;      /* True for a temporary index */
  sqlite3 *db = pParse->db;







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**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.290 2004/12/14 03:34:34 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.


*/
void sqlite3BeginParse(Parse *pParse, int explainFlag){
  pParse->explain = explainFlag;
  pParse->nVar = 0;
}

/*
................................................................................
      sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->cookieGoto);
    }

    /* Add a No-op that contains the complete text of the compiled SQL
    ** statement as its P3 argument.  This does not change the functionality
    ** of the program. 
    **
    ** This is used to implement sqlite3_trace().
    */
    sqlite3VdbeOp3(v, OP_Noop, 0, 0, pParse->zSql, pParse->zTail-pParse->zSql);
  }


  /* Get the VDBE program ready for execution
  */
................................................................................

/*
** The token *pName contains the name of a database (either "main" or
** "temp" or the name of an attached db). This routine returns the
** index of the named database in db->aDb[], or -1 if the named db 
** does not exist.
*/
static int findDb(sqlite3 *db, Token *pName){
  int i;         /* Database number */
  int n;         /* Number of characters in the name */
  Db *pDb;       /* A database whose name space is being searched */
  char *zName;   /* Name we are searching for */

  zName = sqlite3NameFromToken(pName);
  if( zName ){
................................................................................
  Token *pName1,   /* First part of the name of the table or view */
  Token *pName2,   /* Second part of the name of the table or view */
  int isTemp,      /* True if this is a TEMP table */
  int isView       /* True if this is a VIEW */
){
  Table *pTable;
  Index *pIdx;
  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:
................................................................................
  ** created in.
  */
  iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
  if( iDb<0 ) return;
  if( isTemp && iDb>1 ){
    /* If creating a temp table, the name may not be qualified */
    sqlite3ErrorMsg(pParse, "temporary table name must be unqualified");

    return;
  }
  if( isTemp ) iDb = 1;

  pParse->sNameToken = *pName;
  zName = sqlite3NameFromToken(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( isTemp ){
        code = SQLITE_CREATE_TEMP_VIEW;
      }else{
        code = SQLITE_CREATE_VIEW;
      }
................................................................................
      if( isTemp ){
        code = SQLITE_CREATE_TEMP_TABLE;
      }else{
        code = SQLITE_CREATE_TABLE;
      }
    }
    if( 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
  ** it does.
  */
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ) return;
  pTable = sqlite3FindTable(db, zName, db->aDb[iDb].zName);
  if( pTable ){
    sqlite3ErrorMsg(pParse, "table %T already exists", pName);
    goto begin_table_error;

  }
  if( (pIdx = sqlite3FindIndex(db, zName, 0))!=0 && 
      ( iDb==0 || !db->init.busy) ){
    sqlite3ErrorMsg(pParse, "there is already an index named %s", zName);
    goto begin_table_error;

  }
  pTable = sqliteMalloc( sizeof(Table) );
  if( pTable==0 ){
    pParse->rc = SQLITE_NOMEM;
    pParse->nErr++;
    goto begin_table_error;

  }
  pTable->zName = zName;
  pTable->nCol = 0;
  pTable->aCol = 0;
  pTable->iPKey = -1;
  pTable->pIndex = 0;
  pTable->iDb = iDb;
................................................................................
    sqlite3OpenMasterTable(v, iDb);
    sqlite3VdbeAddOp(v, OP_NewRecno, 0, 0);
    sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
    sqlite3VdbeAddOp(v, OP_String8, 0, 0);
    sqlite3VdbeAddOp(v, OP_PutIntKey, 0, 0);
    sqlite3VdbeAddOp(v, OP_Close, 0, 0);
  }

  /* Normal (non-error) return. */
  return;

  /* If an error occurs, we jump here */
begin_table_error:
  sqliteFree(zName);
  return;
}

/*
** Add a new column to the table currently being constructed.
**
** The parser calls this routine once for each column declaration
** in a CREATE TABLE statement.  sqlite3StartTable() gets called
................................................................................
** most recently added column of the table is the primary key.
**
** A table can have at most one primary key.  If the table already has
** a primary key (and this is the second primary key) then create an
** error.
**
** If the PRIMARY KEY is on a single column whose datatype is INTEGER,
** then we will try to use that column as the rowid.  Set the Table.iPKey


** field of the table under construction to be the index of the
** INTEGER PRIMARY KEY column.  Table.iPKey is set to -1 if there is
** no INTEGER PRIMARY KEY.
**
** If the key is not an INTEGER PRIMARY KEY, then create a unique
** index for the key.  No index is created for INTEGER PRIMARY KEYs.
*/
................................................................................
  sqlite3VdbeAddOp(v, OP_Next, iTab, addr1+1);
  sqlite3VdbeChangeP2(v, addr1, sqlite3VdbeCurrentAddr(v));
  sqlite3VdbeAddOp(v, OP_Close, iTab, 0);
  sqlite3VdbeAddOp(v, OP_Close, iIdx, 0);
}

/*
** Create a new index for an SQL table.  pName1.pName2 is the name of the index 
** and pTblList is the name of the table that is to be indexed.  Both will 
** be NULL for a primary key or an index that is created to satisfy a
** UNIQUE constraint.  If pTable and pIndex are NULL, use pParse->pNewTable
** as the table to be indexed.  pParse->pNewTable is a table that is
** currently being constructed by a CREATE TABLE statement.
**
** pList is a list of columns to be indexed.  pList will be NULL if this
** is a primary key or unique-constraint on the most recent column added
** to the table currently under construction.  
*/
void sqlite3CreateIndex(
  Parse *pParse,     /* All information about this parse */
  Token *pName1,     /* First part of index name. May be NULL */
  Token *pName2,     /* Second part of index name. May be NULL */
  SrcList *pTblName, /* Table to index. Use pParse->pNewTable if 0 */
  ExprList *pList,   /* A list of columns to be indexed */
  int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  Token *pStart,     /* The CREATE token that begins a CREATE TABLE statement */
  Token *pEnd        /* The ")" that closes the CREATE INDEX statement */
){
  Table *pTab = 0;   /* Table to be indexed */
  Index *pIndex = 0; /* The index to be created */
  char *zName = 0;
  int i, j;
  Token nullId;    /* Fake token for an empty ID list */
  DbFixer sFix;    /* For assigning database names to pTable */
  int isTemp;      /* True for a temporary index */
  sqlite3 *db = pParse->db;

Changes to src/delete.c.

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**
**    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.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle DELETE FROM statements.
**
** $Id: delete.c,v 1.92 2004/12/07 14:06:13 drh Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................
  sqlite3VdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
  VdbeComment((v, "# %s", pTab->zName));
  sqlite3VdbeAddOp(v, OP_SetNumColumns, iCur, pTab->nCol);
}


/*
** Process a DELETE FROM statement.




*/
void sqlite3DeleteFrom(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */







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**
**    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.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.93 2004/12/14 03:34:34 drh Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................
  sqlite3VdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
  VdbeComment((v, "# %s", pTab->zName));
  sqlite3VdbeAddOp(v, OP_SetNumColumns, iCur, pTab->nCol);
}


/*
** Generate code for a DELETE FROM statement.
**
**     DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
**                 \________/       \________________/
**                  pTabList              pWhere
*/
void sqlite3DeleteFrom(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */

Changes to src/where.c.

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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.
**
** $Id: where.c,v 1.120 2004/11/23 01:47:31 drh Exp $
*/
#include "sqliteInt.h"

/*
** The query generator uses an array of instances of this structure to
** help it analyze the subexpressions of the WHERE clause.  Each WHERE
** clause subexpression is separated from the others by an AND operator.
................................................................................
**
** Consider the term t2.z='ok' in the following queries:
**
**   (1)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x WHERE t2.z='ok'
**   (2)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x AND t2.z='ok'
**   (3)  SELECT * FROM t1, t2 WHERE t1.a=t2.x AND t2.z='ok'
**
** The t2.z='ok' is disabled in the in (2) because it did not originate
** in the ON clause.  The term is disabled in (3) because it is not part
** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
**
** Disabling a term causes that term to not be tested in the inner loop
** of the join.  Disabling is an optimization.  We would get the correct
** results if nothing were ever disabled, but joins might run a little
** slower.  The trick is to disable as much as we can without disabling







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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.
**
** $Id: where.c,v 1.121 2004/12/14 03:34:34 drh Exp $
*/
#include "sqliteInt.h"

/*
** The query generator uses an array of instances of this structure to
** help it analyze the subexpressions of the WHERE clause.  Each WHERE
** clause subexpression is separated from the others by an AND operator.
................................................................................
**
** Consider the term t2.z='ok' in the following queries:
**
**   (1)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x WHERE t2.z='ok'
**   (2)  SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.x AND t2.z='ok'
**   (3)  SELECT * FROM t1, t2 WHERE t1.a=t2.x AND t2.z='ok'
**
** The t2.z='ok' is disabled in the in (2) because it originates
** in the ON clause.  The term is disabled in (3) because it is not part
** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
**
** Disabling a term causes that term to not be tested in the inner loop
** of the join.  Disabling is an optimization.  We would get the correct
** results if nothing were ever disabled, but joins might run a little
** slower.  The trick is to disable as much as we can without disabling