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Diffstat (limited to 'lib/libsqlite3/src/alter.c')
| -rw-r--r-- | lib/libsqlite3/src/alter.c | 832 |
1 files changed, 0 insertions, 832 deletions
diff --git a/lib/libsqlite3/src/alter.c b/lib/libsqlite3/src/alter.c deleted file mode 100644 index 2b043ef158b..00000000000 --- a/lib/libsqlite3/src/alter.c +++ /dev/null @@ -1,832 +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. -*/ -#include "sqliteInt.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 NotUsed, - 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_context_db_handle(context); - - UNUSED_PARAMETER(NotUsed); - - /* The principle used to locate the table name in the CREATE TABLE - ** statement is that the table name is the first non-space token that - ** is immediately followed by a TK_LP or TK_USING token. - */ - 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 = (char*)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\"%w\"%s", (int)(((u8*)tname.z) - zSql), - zSql, zTableName, tname.z+tname.n); - sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC); - } -} - -/* -** This C function implements an SQL user function that is used by SQL code -** generated by the ALTER TABLE ... RENAME command to modify the definition -** of any foreign key constraints that use the table being renamed as the -** parent table. It is passed three arguments: -** -** 1) The complete text of the CREATE TABLE statement being modified, -** 2) The old name of the table being renamed, and -** 3) The new name of the table being renamed. -** -** It returns the new CREATE TABLE statement. For example: -** -** sqlite_rename_parent('CREATE TABLE t1(a REFERENCES t2)', 't2', 't3') -** -> 'CREATE TABLE t1(a REFERENCES t3)' -*/ -#ifndef SQLITE_OMIT_FOREIGN_KEY -static void renameParentFunc( - sqlite3_context *context, - int NotUsed, - sqlite3_value **argv -){ - sqlite3 *db = sqlite3_context_db_handle(context); - char *zOutput = 0; - char *zResult; - unsigned char const *zInput = sqlite3_value_text(argv[0]); - unsigned char const *zOld = sqlite3_value_text(argv[1]); - unsigned char const *zNew = sqlite3_value_text(argv[2]); - - unsigned const char *z; /* Pointer to token */ - int n; /* Length of token z */ - int token; /* Type of token */ - - UNUSED_PARAMETER(NotUsed); - if( zInput==0 || zOld==0 ) return; - for(z=zInput; *z; z=z+n){ - n = sqlite3GetToken(z, &token); - if( token==TK_REFERENCES ){ - char *zParent; - do { - z += n; - n = sqlite3GetToken(z, &token); - }while( token==TK_SPACE ); - - if( token==TK_ILLEGAL ) break; - zParent = sqlite3DbStrNDup(db, (const char *)z, n); - if( zParent==0 ) break; - sqlite3Dequote(zParent); - if( 0==sqlite3StrICmp((const char *)zOld, zParent) ){ - char *zOut = sqlite3MPrintf(db, "%s%.*s\"%w\"", - (zOutput?zOutput:""), (int)(z-zInput), zInput, (const char *)zNew - ); - sqlite3DbFree(db, zOutput); - zOutput = zOut; - zInput = &z[n]; - } - sqlite3DbFree(db, zParent); - } - } - - zResult = sqlite3MPrintf(db, "%s%s", (zOutput?zOutput:""), zInput), - sqlite3_result_text(context, zResult, -1, SQLITE_DYNAMIC); - sqlite3DbFree(db, zOutput); -} -#endif - -#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 NotUsed, - 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_context_db_handle(context); - - UNUSED_PARAMETER(NotUsed); - - /* The principle used to locate the table name in the CREATE TRIGGER - ** statement is that the table name is the first token that is immediately - ** preceded by either TK_ON or TK_DOT and immediately 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 = (char*)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\"%w\"%s", (int)(((u8*)tname.z) - zSql), - zSql, zTableName, tname.z+tname.n); - sqlite3_result_text(context, zRet, -1, SQLITE_DYNAMIC); - } -} -#endif /* !SQLITE_OMIT_TRIGGER */ - -/* -** Register built-in functions used to help implement ALTER TABLE -*/ -void sqlite3AlterFunctions(void){ - static SQLITE_WSD FuncDef aAlterTableFuncs[] = { - FUNCTION(sqlite_rename_table, 2, 0, 0, renameTableFunc), -#ifndef SQLITE_OMIT_TRIGGER - FUNCTION(sqlite_rename_trigger, 2, 0, 0, renameTriggerFunc), -#endif -#ifndef SQLITE_OMIT_FOREIGN_KEY - FUNCTION(sqlite_rename_parent, 3, 0, 0, renameParentFunc), -#endif - }; - int i; - FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions); - FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aAlterTableFuncs); - - for(i=0; i<ArraySize(aAlterTableFuncs); i++){ - sqlite3FuncDefInsert(pHash, &aFunc[i]); - } -} - -/* -** This function is used to create the text of expressions of the form: -** -** name=<constant1> OR name=<constant2> OR ... -** -** If argument zWhere is NULL, then a pointer string containing the text -** "name=<constant>" is returned, where <constant> is the quoted version -** of the string passed as argument zConstant. The returned buffer is -** allocated using sqlite3DbMalloc(). It is the responsibility of the -** caller to ensure that it is eventually freed. -** -** If argument zWhere is not NULL, then the string returned is -** "<where> OR name=<constant>", where <where> is the contents of zWhere. -** In this case zWhere is passed to sqlite3DbFree() before returning. -** -*/ -static char *whereOrName(sqlite3 *db, char *zWhere, char *zConstant){ - char *zNew; - if( !zWhere ){ - zNew = sqlite3MPrintf(db, "name=%Q", zConstant); - }else{ - zNew = sqlite3MPrintf(db, "%s OR name=%Q", zWhere, zConstant); - sqlite3DbFree(db, zWhere); - } - return zNew; -} - -#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER) -/* -** Generate the text of a WHERE expression which can be used to select all -** tables that have foreign key constraints that refer to table pTab (i.e. -** constraints for which pTab is the parent table) from the sqlite_master -** table. -*/ -static char *whereForeignKeys(Parse *pParse, Table *pTab){ - FKey *p; - char *zWhere = 0; - for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){ - zWhere = whereOrName(pParse->db, zWhere, p->pFrom->zName); - } - return zWhere; -} -#endif - -/* -** 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; - 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=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){ - if( pTrig->pSchema==pTempSchema ){ - zWhere = whereOrName(db, zWhere, pTrig->zName); - } - } - } - if( zWhere ){ - char *zNew = sqlite3MPrintf(pParse->db, "type='trigger' AND (%s)", zWhere); - sqlite3DbFree(pParse->db, zWhere); - zWhere = zNew; - } - 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( NEVER(v==0) ) 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=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){ - int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema); - assert( iTrigDb==iDb || iTrigDb==1 ); - sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->zName, 0); - } -#endif - - /* Drop the table and index from the internal schema. */ - sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0); - - /* Reload the table, index and permanent trigger schemas. */ - zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName); - if( !zWhere ) return; - sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere); - -#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 ){ - sqlite3VdbeAddParseSchemaOp(v, 1, zWhere); - } -#endif -} - -/* -** Parameter zName is the name of a table that is about to be altered -** (either with ALTER TABLE ... RENAME TO or ALTER TABLE ... ADD COLUMN). -** If the table is a system table, this function leaves an error message -** in pParse->zErr (system tables may not be altered) and returns non-zero. -** -** Or, if zName is not a system table, zero is returned. -*/ -static int isSystemTable(Parse *pParse, const char *zName){ - if( sqlite3Strlen30(zName)>6 && 0==sqlite3StrNICmp(zName, "sqlite_", 7) ){ - sqlite3ErrorMsg(pParse, "table %s may not be altered", zName); - return 1; - } - return 0; -} - -/* -** 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 - VTable *pVTab = 0; /* Non-zero if this is a v-tab with an xRename() */ - int savedDbFlags; /* Saved value of db->flags */ - - savedDbFlags = db->flags; - if( NEVER(db->mallocFailed) ) goto exit_rename_table; - assert( pSrc->nSrc==1 ); - assert( sqlite3BtreeHoldsAllMutexes(pParse->db) ); - - pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]); - if( !pTab ) goto exit_rename_table; - iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema); - zDb = db->aDb[iDb].zName; - db->flags |= SQLITE_PreferBuiltin; - - /* 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( SQLITE_OK!=isSystemTable(pParse, 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) ){ - pVTab = sqlite3GetVTable(db, pTab); - if( pVTab->pVtab->pModule->xRename==0 ){ - pVTab = 0; - } - } -#endif - - /* Begin a transaction 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, pVTab!=0, iDb); - sqlite3ChangeCookie(pParse, 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( pVTab ){ - int i = ++pParse->nMem; - sqlite3VdbeLoadString(v, i, zName); - sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB); - sqlite3MayAbort(pParse); - } -#endif - - /* figure out how many UTF-8 characters are in zName */ - zTabName = pTab->zName; - nTabName = sqlite3Utf8CharLen(zTabName, -1); - -#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER) - if( db->flags&SQLITE_ForeignKeys ){ - /* If foreign-key support is enabled, rewrite the CREATE TABLE - ** statements corresponding to all child tables of foreign key constraints - ** for which the renamed table is the parent table. */ - if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){ - sqlite3NestedParse(pParse, - "UPDATE \"%w\".%s SET " - "sql = sqlite_rename_parent(sql, %Q, %Q) " - "WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere); - sqlite3DbFree(db, zWhere); - } - } -#endif - - /* 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 COLLATE nocase 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 \"%w\".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); - sqlite3DbFree(db, zWhere); - } -#endif - -#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER) - if( db->flags&SQLITE_ForeignKeys ){ - FKey *p; - for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){ - Table *pFrom = p->pFrom; - if( pFrom!=pTab ){ - reloadTableSchema(pParse, p->pFrom, pFrom->zName); - } - } - } -#endif - - /* Drop and reload the internal table schema. */ - reloadTableSchema(pParse, pTab, zName); - -exit_rename_table: - sqlite3SrcListDelete(db, pSrc); - sqlite3DbFree(db, zName); - db->flags = savedDbFlags; -} - - -/* -** Generate code to make sure the file format number is at least minFormat. -** The generated code will increase the file format number if necessary. -*/ -void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){ - Vdbe *v; - v = sqlite3GetVdbe(pParse); - /* The VDBE should have been allocated before this routine is called. - ** If that allocation failed, we would have quit before reaching this - ** point */ - if( ALWAYS(v) ){ - int r1 = sqlite3GetTempReg(pParse); - int r2 = sqlite3GetTempReg(pParse); - int addr1; - sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT); - sqlite3VdbeUsesBtree(v, iDb); - sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2); - addr1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1); - sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); VdbeCoverage(v); - sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2); - sqlite3VdbeJumpHere(v, addr1); - sqlite3ReleaseTempReg(pParse, r1); - sqlite3ReleaseTempReg(pParse, r2); - } -} - -/* -** 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; */ - - db = pParse->db; - if( pParse->nErr || db->mallocFailed ) return; - pNew = pParse->pNewTable; - assert( pNew ); - - assert( sqlite3BtreeHoldsAllMutexes(db) ); - iDb = sqlite3SchemaToIndex(db, pNew->pSchema); - zDb = db->aDb[iDb].zName; - zTab = &pNew->zName[16]; /* Skip the "sqlite_altertab_" prefix on the name */ - 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->colFlags & COLFLAG_PRIMKEY ){ - sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column"); - return; - } - if( pNew->pIndex ){ - sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column"); - return; - } - if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){ - sqlite3ErrorMsg(pParse, - "Cannot add a REFERENCES column with non-NULL default value"); - 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 = 0; - int rc; - rc = sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_BLOB, &pVal); - assert( rc==SQLITE_OK || rc==SQLITE_NOMEM ); - if( rc!=SQLITE_OK ){ - 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]; - int savedDbFlags = db->flags; - while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){ - *zEnd-- = '\0'; - } - db->flags |= SQLITE_PreferBuiltin; - sqlite3NestedParse(pParse, - "UPDATE \"%w\".%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 - ); - sqlite3DbFree(db, zCol); - db->flags = savedDbFlags; - } - - /* 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 = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]); - 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; - } - if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){ - 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. But modify - ** the name by adding an "sqlite_altertab_" prefix. By adding this - ** prefix, we insure that the name will not collide with an existing - ** table because user table are not allowed to have the "sqlite_" - ** prefix on their name. - */ - 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 = sqlite3MPrintf(db, "sqlite_altertab_%s", 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; - pCol->zDflt = 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(pParse, iDb); - -exit_begin_add_column: - sqlite3SrcListDelete(db, pSrc); - return; -} -#endif /* SQLITE_ALTER_TABLE */ |