--- a/engine/sqlite/src/alter.cpp Wed May 26 10:44:32 2010 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,629 +0,0 @@
-/*
-** 2005 February 15
-**
-** The author disclaims copyright to this source code. In place of
-** a legal notice, here is a blessing:
-**
-** 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 used to generate VDBE code
-** that implements the ALTER TABLE command.
-**
-** $Id: alter.cpp 1282 2008-11-13 09:31:33Z LarsPson $
-*/
-#include "sqliteInt.h"
-#include <ctype.h>
-
-/*
-** The code in this file only exists if we are not omitting the
-** ALTER TABLE logic from the build.
-*/
-#ifndef SQLITE_OMIT_ALTERTABLE
-
-
-/*
-** This function is used by SQL generated to implement the
-** ALTER TABLE command. The first argument is the text of a CREATE TABLE or
-** CREATE INDEX command. The second is a table name. The table name in
-** the CREATE TABLE or CREATE INDEX statement is replaced with the third
-** argument and the result returned. Examples:
-**
-** sqlite_rename_table('CREATE TABLE abc(a, b, c)', 'def')
-** -> 'CREATE TABLE def(a, b, c)'
-**
-** sqlite_rename_table('CREATE INDEX i ON abc(a)', 'def')
-** -> 'CREATE INDEX i ON def(a, b, c)'
-*/
-static void renameTableFunc(
- sqlite3_context *context,
- int argc,
- sqlite3_value **argv
-){
- unsigned char const *zSql = sqlite3_value_text(argv[0]);
- unsigned char const *zTableName = sqlite3_value_text(argv[1]);
-
- int token;
- Token tname;
- unsigned char const *zCsr = zSql;
- int len = 0;
- char *zRet;
-
- sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-
- /* The principle used to locate the table name in the CREATE TABLE
- ** statement is that the table name is the first token that is immediatedly
- ** followed by a left parenthesis - TK_LP - or "USING" TK_USING.
- */
- if( zSql ){
- do {
- if( !*zCsr ){
- /* Ran out of input before finding an opening bracket. Return NULL. */
- return;
- }
-
- /* Store the token that zCsr points to in tname. */
- tname.z = zCsr;
- tname.n = len;
-
- /* Advance zCsr to the next token. Store that token type in 'token',
- ** and its length in 'len' (to be used next iteration of this loop).
- */
- do {
- zCsr += len;
- len = sqlite3GetToken(zCsr, &token);
- } while( token==TK_SPACE );
- assert( len>0 );
- } while( token!=TK_LP && token!=TK_USING );
-
- zRet = sqlite3MPrintf(db, "%.*s%Q%s", tname.z - zSql, zSql,
- zTableName, tname.z+tname.n);
- sqlite3_result_text(context, zRet, -1, sqlite3_free);
- }
-}
-
-#ifndef SQLITE_OMIT_TRIGGER
-/* This function is used by SQL generated to implement the
-** ALTER TABLE command. The first argument is the text of a CREATE TRIGGER
-** statement. The second is a table name. The table name in the CREATE
-** TRIGGER statement is replaced with the third argument and the result
-** returned. This is analagous to renameTableFunc() above, except for CREATE
-** TRIGGER, not CREATE INDEX and CREATE TABLE.
-*/
-static void renameTriggerFunc(
- sqlite3_context *context,
- int argc,
- sqlite3_value **argv
-){
- unsigned char const *zSql = sqlite3_value_text(argv[0]);
- unsigned char const *zTableName = sqlite3_value_text(argv[1]);
-
- int token;
- Token tname;
- int dist = 3;
- unsigned char const *zCsr = zSql;
- int len = 0;
- char *zRet;
-
- sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-
- /* The principle used to locate the table name in the CREATE TRIGGER
- ** statement is that the table name is the first token that is immediatedly
- ** preceded by either TK_ON or TK_DOT and immediatedly followed by one
- ** of TK_WHEN, TK_BEGIN or TK_FOR.
- */
- if( zSql ){
- do {
-
- if( !*zCsr ){
- /* Ran out of input before finding the table name. Return NULL. */
- return;
- }
-
- /* Store the token that zCsr points to in tname. */
- tname.z = zCsr;
- tname.n = len;
-
- /* Advance zCsr to the next token. Store that token type in 'token',
- ** and its length in 'len' (to be used next iteration of this loop).
- */
- do {
- zCsr += len;
- len = sqlite3GetToken(zCsr, &token);
- }while( token==TK_SPACE );
- assert( len>0 );
-
- /* Variable 'dist' stores the number of tokens read since the most
- ** recent TK_DOT or TK_ON. This means that when a WHEN, FOR or BEGIN
- ** token is read and 'dist' equals 2, the condition stated above
- ** to be met.
- **
- ** Note that ON cannot be a database, table or column name, so
- ** there is no need to worry about syntax like
- ** "CREATE TRIGGER ... ON ON.ON BEGIN ..." etc.
- */
- dist++;
- if( token==TK_DOT || token==TK_ON ){
- dist = 0;
- }
- } while( dist!=2 || (token!=TK_WHEN && token!=TK_FOR && token!=TK_BEGIN) );
-
- /* Variable tname now contains the token that is the old table-name
- ** in the CREATE TRIGGER statement.
- */
- zRet = sqlite3MPrintf(db, "%.*s%Q%s", tname.z - zSql, zSql,
- zTableName, tname.z+tname.n);
- sqlite3_result_text(context, zRet, -1, sqlite3_free);
- }
-}
-#endif /* !SQLITE_OMIT_TRIGGER */
-
-/*
-** Register built-in functions used to help implement ALTER TABLE
-*/
-void sqlite3AlterFunctions(sqlite3 *db){
- static const struct {
- char *zName;
- signed char nArg;
- void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
- } aFuncs[] = {
- { "sqlite_rename_table", 2, renameTableFunc},
-#ifndef SQLITE_OMIT_TRIGGER
- { "sqlite_rename_trigger", 2, renameTriggerFunc},
-#endif
- };
- int i;
-
- for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
- sqlite3CreateFunc(db, aFuncs[i].zName, aFuncs[i].nArg,
- SQLITE_UTF8, (void *)db, aFuncs[i].xFunc, 0, 0);
- }
-}
-
-/*
-** Generate the text of a WHERE expression which can be used to select all
-** temporary triggers on table pTab from the sqlite_temp_master table. If
-** table pTab has no temporary triggers, or is itself stored in the
-** temporary database, NULL is returned.
-*/
-static char *whereTempTriggers(Parse *pParse, Table *pTab){
- Trigger *pTrig;
- char *zWhere = 0;
- char *tmp = 0;
- const Schema *pTempSchema = pParse->db->aDb[1].pSchema; /* Temp db schema */
-
- /* If the table is not located in the temp-db (in which case NULL is
- ** returned, loop through the tables list of triggers. For each trigger
- ** that is not part of the temp-db schema, add a clause to the WHERE
- ** expression being built up in zWhere.
- */
- if( pTab->pSchema!=pTempSchema ){
- sqlite3 *db = pParse->db;
- for( pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext ){
- if( pTrig->pSchema==pTempSchema ){
- if( !zWhere ){
- zWhere = sqlite3MPrintf(db, "name=%Q", pTrig->name);
- }else{
- tmp = zWhere;
- zWhere = sqlite3MPrintf(db, "%s OR name=%Q", zWhere, pTrig->name);
- sqlite3_free(tmp);
- }
- }
- }
- }
- return zWhere;
-}
-
-/*
-** Generate code to drop and reload the internal representation of table
-** pTab from the database, including triggers and temporary triggers.
-** Argument zName is the name of the table in the database schema at
-** the time the generated code is executed. This can be different from
-** pTab->zName if this function is being called to code part of an
-** "ALTER TABLE RENAME TO" statement.
-*/
-static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
- Vdbe *v;
- char *zWhere;
- int iDb; /* Index of database containing pTab */
-#ifndef SQLITE_OMIT_TRIGGER
- Trigger *pTrig;
-#endif
-
- v = sqlite3GetVdbe(pParse);
- if( !v ) return;
- assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
- iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
- assert( iDb>=0 );
-
-#ifndef SQLITE_OMIT_TRIGGER
- /* Drop any table triggers from the internal schema. */
- for(pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext){
- int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
- assert( iTrigDb==iDb || iTrigDb==1 );
- sqlite3VdbeOp3(v, OP_DropTrigger, iTrigDb, 0, pTrig->name, 0);
- }
-#endif
-
- /* Drop the table and index from the internal schema */
- sqlite3VdbeOp3(v, OP_DropTable, iDb, 0, pTab->zName, 0);
-
- /* Reload the table, index and permanent trigger schemas. */
- zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
- if( !zWhere ) return;
- sqlite3VdbeOp3(v, OP_ParseSchema, iDb, 0, zWhere, P3_DYNAMIC);
-
-#ifndef SQLITE_OMIT_TRIGGER
- /* Now, if the table is not stored in the temp database, reload any temp
- ** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined.
- */
- if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
- sqlite3VdbeOp3(v, OP_ParseSchema, 1, 0, zWhere, P3_DYNAMIC);
- }
-#endif
-}
-
-/*
-** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
-** command.
-*/
-void sqlite3AlterRenameTable(
- Parse *pParse, /* Parser context. */
- SrcList *pSrc, /* The table to rename. */
- Token *pName /* The new table name. */
-){
- int iDb; /* Database that contains the table */
- char *zDb; /* Name of database iDb */
- Table *pTab; /* Table being renamed */
- char *zName = 0; /* NULL-terminated version of pName */
- sqlite3 *db = pParse->db; /* Database connection */
- int nTabName; /* Number of UTF-8 characters in zTabName */
- const char *zTabName; /* Original name of the table */
- Vdbe *v;
-#ifndef SQLITE_OMIT_TRIGGER
- char *zWhere = 0; /* Where clause to locate temp triggers */
-#endif
- int isVirtualRename = 0; /* True if this is a v-table with an xRename() */
-
- if( db->mallocFailed ) goto exit_rename_table;
- assert( pSrc->nSrc==1 );
- assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
-
- pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
- if( !pTab ) goto exit_rename_table;
- iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
- zDb = db->aDb[iDb].zName;
-
- /* Get a NULL terminated version of the new table name. */
- zName = sqlite3NameFromToken(db, pName);
- if( !zName ) goto exit_rename_table;
-
- /* Check that a table or index named 'zName' does not already exist
- ** in database iDb. If so, this is an error.
- */
- if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
- sqlite3ErrorMsg(pParse,
- "there is already another table or index with this name: %s", zName);
- goto exit_rename_table;
- }
-
- /* Make sure it is not a system table being altered, or a reserved name
- ** that the table is being renamed to.
- */
- if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
- sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
- goto exit_rename_table;
- }
- if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
- goto exit_rename_table;
- }
-
-#ifndef SQLITE_OMIT_VIEW
- if( pTab->pSelect ){
- sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
- goto exit_rename_table;
- }
-#endif
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
- /* Invoke the authorization callback. */
- if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
- goto exit_rename_table;
- }
-#endif
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
- if( sqlite3ViewGetColumnNames(pParse, pTab) ){
- goto exit_rename_table;
- }
- if( IsVirtual(pTab) && pTab->pMod->pModule->xRename ){
- isVirtualRename = 1;
- }
-#endif
-
- /* Begin a transaction and code the VerifyCookie for database iDb.
- ** Then modify the schema cookie (since the ALTER TABLE modifies the
- ** schema). Open a statement transaction if the table is a virtual
- ** table.
- */
- v = sqlite3GetVdbe(pParse);
- if( v==0 ){
- goto exit_rename_table;
- }
- sqlite3BeginWriteOperation(pParse, isVirtualRename, iDb);
- sqlite3ChangeCookie(db, v, iDb);
-
- /* If this is a virtual table, invoke the xRename() function if
- ** one is defined. The xRename() callback will modify the names
- ** of any resources used by the v-table implementation (including other
- ** SQLite tables) that are identified by the name of the virtual table.
- */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
- if( isVirtualRename ){
- sqlite3VdbeOp3(v, OP_String8, 0, 0, zName, 0);
- sqlite3VdbeOp3(v, OP_VRename, 0, 0, (const char*)pTab->pVtab, P3_VTAB);
- }
-#endif
-
- /* figure out how many UTF-8 characters are in zName */
- zTabName = pTab->zName;
- nTabName = sqlite3Utf8CharLen(zTabName, -1);
-
- /* Modify the sqlite_master table to use the new table name. */
- sqlite3NestedParse(pParse,
- "UPDATE %Q.%s SET "
-#ifdef SQLITE_OMIT_TRIGGER
- "sql = sqlite_rename_table(sql, %Q), "
-#else
- "sql = CASE "
- "WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
- "ELSE sqlite_rename_table(sql, %Q) END, "
-#endif
- "tbl_name = %Q, "
- "name = CASE "
- "WHEN type='table' THEN %Q "
- "WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
- "'sqlite_autoindex_' || %Q || substr(name,%d+18) "
- "ELSE name END "
- "WHERE tbl_name=%Q AND "
- "(type='table' OR type='index' OR type='trigger');",
- zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
-#ifndef SQLITE_OMIT_TRIGGER
- zName,
-#endif
- zName, nTabName, zTabName
- );
-
-#ifndef SQLITE_OMIT_AUTOINCREMENT
- /* If the sqlite_sequence table exists in this database, then update
- ** it with the new table name.
- */
- if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
- sqlite3NestedParse(pParse,
- "UPDATE %Q.sqlite_sequence set name = %Q WHERE name = %Q",
- zDb, zName, pTab->zName);
- }
-#endif
-
-#ifndef SQLITE_OMIT_TRIGGER
- /* If there are TEMP triggers on this table, modify the sqlite_temp_master
- ** table. Don't do this if the table being ALTERed is itself located in
- ** the temp database.
- */
- if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
- sqlite3NestedParse(pParse,
- "UPDATE sqlite_temp_master SET "
- "sql = sqlite_rename_trigger(sql, %Q), "
- "tbl_name = %Q "
- "WHERE %s;", zName, zName, zWhere);
- sqlite3_free(zWhere);
- }
-#endif
-
- /* Drop and reload the internal table schema. */
- reloadTableSchema(pParse, pTab, zName);
-
-exit_rename_table:
- sqlite3SrcListDelete(pSrc);
- sqlite3_free(zName);
-}
-
-
-/*
-** This function is called after an "ALTER TABLE ... ADD" statement
-** has been parsed. Argument pColDef contains the text of the new
-** column definition.
-**
-** The Table structure pParse->pNewTable was extended to include
-** the new column during parsing.
-*/
-void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
- Table *pNew; /* Copy of pParse->pNewTable */
- Table *pTab; /* Table being altered */
- int iDb; /* Database number */
- const char *zDb; /* Database name */
- const char *zTab; /* Table name */
- char *zCol; /* Null-terminated column definition */
- Column *pCol; /* The new column */
- Expr *pDflt; /* Default value for the new column */
- sqlite3 *db; /* The database connection; */
-
- if( pParse->nErr ) return;
- pNew = pParse->pNewTable;
- assert( pNew );
-
- db = pParse->db;
- assert( sqlite3BtreeHoldsAllMutexes(db) );
- iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
- zDb = db->aDb[iDb].zName;
- zTab = pNew->zName;
- pCol = &pNew->aCol[pNew->nCol-1];
- pDflt = pCol->pDflt;
- pTab = sqlite3FindTable(db, zTab, zDb);
- assert( pTab );
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
- /* Invoke the authorization callback. */
- if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
- return;
- }
-#endif
-
- /* If the default value for the new column was specified with a
- ** literal NULL, then set pDflt to 0. This simplifies checking
- ** for an SQL NULL default below.
- */
- if( pDflt && pDflt->op==TK_NULL ){
- pDflt = 0;
- }
-
- /* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
- ** If there is a NOT NULL constraint, then the default value for the
- ** column must not be NULL.
- */
- if( pCol->isPrimKey ){
- sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
- return;
- }
- if( pNew->pIndex ){
- sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
- return;
- }
- if( pCol->notNull && !pDflt ){
- sqlite3ErrorMsg(pParse,
- "Cannot add a NOT NULL column with default value NULL");
- return;
- }
-
- /* Ensure the default expression is something that sqlite3ValueFromExpr()
- ** can handle (i.e. not CURRENT_TIME etc.)
- */
- if( pDflt ){
- sqlite3_value *pVal;
- if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
- db->mallocFailed = 1;
- return;
- }
- if( !pVal ){
- sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
- return;
- }
- sqlite3ValueFree(pVal);
- }
-
- /* Modify the CREATE TABLE statement. */
- zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
- if( zCol ){
- char *zEnd = &zCol[pColDef->n-1];
- while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
- *zEnd-- = '\0';
- }
- sqlite3NestedParse(pParse,
- "UPDATE %Q.%s SET "
- "sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
- "WHERE type = 'table' AND name = %Q",
- zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
- zTab
- );
- sqlite3_free(zCol);
- }
-
- /* If the default value of the new column is NULL, then set the file
- ** format to 2. If the default value of the new column is not NULL,
- ** the file format becomes 3.
- */
- sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
-
- /* Reload the schema of the modified table. */
- reloadTableSchema(pParse, pTab, pTab->zName);
-}
-
-/*
-** This function is called by the parser after the table-name in
-** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument
-** pSrc is the full-name of the table being altered.
-**
-** This routine makes a (partial) copy of the Table structure
-** for the table being altered and sets Parse.pNewTable to point
-** to it. Routines called by the parser as the column definition
-** is parsed (i.e. sqlite3AddColumn()) add the new Column data to
-** the copy. The copy of the Table structure is deleted by tokenize.c
-** after parsing is finished.
-**
-** Routine sqlite3AlterFinishAddColumn() will be called to complete
-** coding the "ALTER TABLE ... ADD" statement.
-*/
-void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
- Table *pNew;
- Table *pTab;
- Vdbe *v;
- int iDb;
- int i;
- int nAlloc;
- sqlite3 *db = pParse->db;
-
- /* Look up the table being altered. */
- assert( pParse->pNewTable==0 );
- assert( sqlite3BtreeHoldsAllMutexes(db) );
- if( db->mallocFailed ) goto exit_begin_add_column;
- pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
- if( !pTab ) goto exit_begin_add_column;
-
-#ifndef SQLITE_OMIT_VIRTUALTABLE
- if( IsVirtual(pTab) ){
- sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
- goto exit_begin_add_column;
- }
-#endif
-
- /* Make sure this is not an attempt to ALTER a view. */
- if( pTab->pSelect ){
- sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
- goto exit_begin_add_column;
- }
-
- assert( pTab->addColOffset>0 );
- iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
-
- /* Put a copy of the Table struct in Parse.pNewTable for the
- ** sqlite3AddColumn() function and friends to modify.
- */
- pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
- if( !pNew ) goto exit_begin_add_column;
- pParse->pNewTable = pNew;
- pNew->nRef = 1;
- pNew->nCol = pTab->nCol;
- assert( pNew->nCol>0 );
- nAlloc = (((pNew->nCol-1)/8)*8)+8;
- assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
- pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
- pNew->zName = sqlite3DbStrDup(db, pTab->zName);
- if( !pNew->aCol || !pNew->zName ){
- db->mallocFailed = 1;
- goto exit_begin_add_column;
- }
- memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
- for(i=0; i<pNew->nCol; i++){
- Column *pCol = &pNew->aCol[i];
- pCol->zName = sqlite3DbStrDup(db, pCol->zName);
- pCol->zColl = 0;
- pCol->zType = 0;
- pCol->pDflt = 0;
- }
- pNew->pSchema = db->aDb[iDb].pSchema;
- pNew->addColOffset = pTab->addColOffset;
- pNew->nRef = 1;
-
- /* Begin a transaction and increment the schema cookie. */
- sqlite3BeginWriteOperation(pParse, 0, iDb);
- v = sqlite3GetVdbe(pParse);
- if( !v ) goto exit_begin_add_column;
- sqlite3ChangeCookie(db, v, iDb);
-
-exit_begin_add_column:
- sqlite3SrcListDelete(pSrc);
- return;
-}
-#endif /* SQLITE_ALTER_TABLE */