diff options
Diffstat (limited to 'src/alter.c')
| -rw-r--r-- | src/alter.c | 2306 |
1 files changed, 2306 insertions, 0 deletions
diff --git a/src/alter.c b/src/alter.c new file mode 100644 index 0000000..ec45e14 --- /dev/null +++ b/src/alter.c @@ -0,0 +1,2306 @@ +/* +** 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 + +/* +** 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 isAlterableTable(Parse *pParse, Table *pTab){ + if( 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) +#ifndef SQLITE_OMIT_VIRTUALTABLE + || (pTab->tabFlags & TF_Eponymous)!=0 + || ( (pTab->tabFlags & TF_Shadow)!=0 + && sqlite3ReadOnlyShadowTables(pParse->db) + ) +#endif + ){ + sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName); + return 1; + } + return 0; +} + +/* +** Generate code to verify that the schemas of database zDb and, if +** bTemp is not true, database "temp", can still be parsed. This is +** called at the end of the generation of an ALTER TABLE ... RENAME ... +** statement to ensure that the operation has not rendered any schema +** objects unusable. +*/ +static void renameTestSchema( + Parse *pParse, /* Parse context */ + const char *zDb, /* Name of db to verify schema of */ + int bTemp, /* True if this is the temp db */ + const char *zWhen, /* "when" part of error message */ + int bNoDQS /* Do not allow DQS in the schema */ +){ + pParse->colNamesSet = 1; + sqlite3NestedParse(pParse, + "SELECT 1 " + "FROM \"%w\"." LEGACY_SCHEMA_TABLE " " + "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" + " AND sql NOT LIKE 'create virtual%%'" + " AND sqlite_rename_test(%Q, sql, type, name, %d, %Q, %d)=NULL ", + zDb, + zDb, bTemp, zWhen, bNoDQS + ); + + if( bTemp==0 ){ + sqlite3NestedParse(pParse, + "SELECT 1 " + "FROM temp." LEGACY_SCHEMA_TABLE " " + "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" + " AND sql NOT LIKE 'create virtual%%'" + " AND sqlite_rename_test(%Q, sql, type, name, 1, %Q, %d)=NULL ", + zDb, zWhen, bNoDQS + ); + } +} + +/* +** Generate VM code to replace any double-quoted strings (but not double-quoted +** identifiers) within the "sql" column of the sqlite_schema table in +** database zDb with their single-quoted equivalents. If argument bTemp is +** not true, similarly update all SQL statements in the sqlite_schema table +** of the temp db. +*/ +static void renameFixQuotes(Parse *pParse, const char *zDb, int bTemp){ + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." LEGACY_SCHEMA_TABLE + " SET sql = sqlite_rename_quotefix(%Q, sql)" + "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" + " AND sql NOT LIKE 'create virtual%%'" , zDb, zDb + ); + if( bTemp==0 ){ + sqlite3NestedParse(pParse, + "UPDATE temp." LEGACY_SCHEMA_TABLE + " SET sql = sqlite_rename_quotefix('temp', sql)" + "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" + " AND sql NOT LIKE 'create virtual%%'" + ); + } +} + +/* +** Generate code to reload the schema for database iDb. And, if iDb!=1, for +** the temp database as well. +*/ +static void renameReloadSchema(Parse *pParse, int iDb, u16 p5){ + Vdbe *v = pParse->pVdbe; + if( v ){ + sqlite3ChangeCookie(pParse, iDb); + sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, iDb, 0, p5); + if( iDb!=1 ) sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, 1, 0, p5); + } +} + +/* +** 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; + VTable *pVTab = 0; /* Non-zero if this is a v-tab with an xRename() */ + + 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].zDbSName; + + /* 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) + || sqlite3IsShadowTableOf(db, pTab, zName) + ){ + 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!=isAlterableTable(pParse, pTab) ){ + goto exit_rename_table; + } + if( SQLITE_OK!=sqlite3CheckObjectName(pParse,zName,"table",zName) ){ + goto exit_rename_table; + } + +#ifndef SQLITE_OMIT_VIEW + if( IsView(pTab) ){ + 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). Call sqlite3MayAbort(), + ** as the scalar functions (e.g. sqlite_rename_table()) invoked by the + ** nested SQL may raise an exception. */ + v = sqlite3GetVdbe(pParse); + if( v==0 ){ + goto exit_rename_table; + } + sqlite3MayAbort(pParse); + + /* figure out how many UTF-8 characters are in zName */ + zTabName = pTab->zName; + nTabName = sqlite3Utf8CharLen(zTabName, -1); + + /* Rewrite all CREATE TABLE, INDEX, TRIGGER or VIEW statements in + ** the schema to use the new table name. */ + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." LEGACY_SCHEMA_TABLE " SET " + "sql = sqlite_rename_table(%Q, type, name, sql, %Q, %Q, %d) " + "WHERE (type!='index' OR tbl_name=%Q COLLATE nocase)" + "AND name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" + , zDb, zDb, zTabName, zName, (iDb==1), zTabName + ); + + /* Update the tbl_name and name columns of the sqlite_schema table + ** as required. */ + sqlite3NestedParse(pParse, + "UPDATE %Q." LEGACY_SCHEMA_TABLE " SET " + "tbl_name = %Q, " + "name = CASE " + "WHEN type='table' THEN %Q " + "WHEN name LIKE 'sqliteX_autoindex%%' ESCAPE 'X' " + " 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, + zName, zName, 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 + + /* If the table being renamed is not itself part of the temp database, + ** edit view and trigger definitions within the temp database + ** as required. */ + if( iDb!=1 ){ + sqlite3NestedParse(pParse, + "UPDATE sqlite_temp_schema SET " + "sql = sqlite_rename_table(%Q, type, name, sql, %Q, %Q, 1), " + "tbl_name = " + "CASE WHEN tbl_name=%Q COLLATE nocase AND " + " sqlite_rename_test(%Q, sql, type, name, 1, 'after rename', 0) " + "THEN %Q ELSE tbl_name END " + "WHERE type IN ('view', 'trigger')" + , zDb, zTabName, zName, zTabName, zDb, zName); + } + + /* 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); + } +#endif + + renameReloadSchema(pParse, iDb, INITFLAG_AlterRename); + renameTestSchema(pParse, zDb, iDb==1, "after rename", 0); + +exit_rename_table: + sqlite3SrcListDelete(db, pSrc); + sqlite3DbFree(db, zName); +} + +/* +** Write code that will raise an error if the table described by +** zDb and zTab is not empty. +*/ +static void sqlite3ErrorIfNotEmpty( + Parse *pParse, /* Parsing context */ + const char *zDb, /* Schema holding the table */ + const char *zTab, /* Table to check for empty */ + const char *zErr /* Error message text */ +){ + sqlite3NestedParse(pParse, + "SELECT raise(ABORT,%Q) FROM \"%w\".\"%w\"", + zErr, zDb, zTab + ); +} + +/* +** 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; */ + Vdbe *v; /* The prepared statement under construction */ + int r1; /* Temporary registers */ + + db = pParse->db; + assert( db->pParse==pParse ); + if( pParse->nErr ) return; + assert( db->mallocFailed==0 ); + pNew = pParse->pNewTable; + assert( pNew ); + + assert( sqlite3BtreeHoldsAllMutexes(db) ); + iDb = sqlite3SchemaToIndex(db, pNew->pSchema); + zDb = db->aDb[iDb].zDbSName; + zTab = &pNew->zName[16]; /* Skip the "sqlite_altertab_" prefix on the name */ + pCol = &pNew->aCol[pNew->nCol-1]; + pDflt = sqlite3ColumnExpr(pNew, pCol); + 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 + + + /* 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( (pCol->colFlags & COLFLAG_GENERATED)==0 ){ + /* 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. + */ + assert( pDflt==0 || pDflt->op==TK_SPAN ); + if( pDflt && pDflt->pLeft->op==TK_NULL ){ + pDflt = 0; + } + assert( IsOrdinaryTable(pNew) ); + if( (db->flags&SQLITE_ForeignKeys) && pNew->u.tab.pFKey && pDflt ){ + sqlite3ErrorIfNotEmpty(pParse, zDb, zTab, + "Cannot add a REFERENCES column with non-NULL default value"); + } + if( pCol->notNull && !pDflt ){ + sqlite3ErrorIfNotEmpty(pParse, zDb, zTab, + "Cannot add a NOT NULL column with default value NULL"); + } + + + /* 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 ){ + assert( db->mallocFailed == 1 ); + return; + } + if( !pVal ){ + sqlite3ErrorIfNotEmpty(pParse, zDb, zTab, + "Cannot add a column with non-constant default"); + } + sqlite3ValueFree(pVal); + } + }else if( pCol->colFlags & COLFLAG_STORED ){ + sqlite3ErrorIfNotEmpty(pParse, zDb, zTab, "cannot add a STORED column"); + } + + + /* 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==';' || sqlite3Isspace(*zEnd)) ){ + *zEnd-- = '\0'; + } + /* substr() operations on characters, but addColOffset is in bytes. So we + ** have to use printf() to translate between these units: */ + assert( IsOrdinaryTable(pTab) ); + assert( IsOrdinaryTable(pNew) ); + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." LEGACY_SCHEMA_TABLE " SET " + "sql = printf('%%.%ds, ',sql) || %Q" + " || substr(sql,1+length(printf('%%.%ds',sql))) " + "WHERE type = 'table' AND name = %Q", + zDb, pNew->u.tab.addColOffset, zCol, pNew->u.tab.addColOffset, + zTab + ); + sqlite3DbFree(db, zCol); + } + + v = sqlite3GetVdbe(pParse); + if( v ){ + /* Make sure the schema version is at least 3. But do not upgrade + ** from less than 3 to 4, as that will corrupt any preexisting DESC + ** index. + */ + r1 = sqlite3GetTempReg(pParse); + sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT); + sqlite3VdbeUsesBtree(v, iDb); + sqlite3VdbeAddOp2(v, OP_AddImm, r1, -2); + sqlite3VdbeAddOp2(v, OP_IfPos, r1, sqlite3VdbeCurrentAddr(v)+2); + VdbeCoverage(v); + sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, 3); + sqlite3ReleaseTempReg(pParse, r1); + + /* Reload the table definition */ + renameReloadSchema(pParse, iDb, INITFLAG_AlterAdd); + + /* Verify that constraints are still satisfied */ + if( pNew->pCheck!=0 + || (pCol->notNull && (pCol->colFlags & COLFLAG_GENERATED)!=0) + || (pTab->tabFlags & TF_Strict)!=0 + ){ + sqlite3NestedParse(pParse, + "SELECT CASE WHEN quick_check GLOB 'CHECK*'" + " THEN raise(ABORT,'CHECK constraint failed')" + " WHEN quick_check GLOB 'non-* value in*'" + " THEN raise(ABORT,'type mismatch on DEFAULT')" + " ELSE raise(ABORT,'NOT NULL constraint failed')" + " END" + " FROM pragma_quick_check(%Q,%Q)" + " WHERE quick_check GLOB 'CHECK*'" + " OR quick_check GLOB 'NULL*'" + " OR quick_check GLOB 'non-* value in*'", + zTab, zDb + ); + } + } +} + +/* +** 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; + 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( IsView(pTab) ){ + sqlite3ErrorMsg(pParse, "Cannot add a column to a view"); + goto exit_begin_add_column; + } + if( SQLITE_OK!=isAlterableTable(pParse, pTab) ){ + goto exit_begin_add_column; + } + + sqlite3MayAbort(pParse); + assert( IsOrdinaryTable(pTab) ); + assert( pTab->u.tab.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->nTabRef = 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 ){ + assert( db->mallocFailed ); + 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->zCnName = sqlite3DbStrDup(db, pCol->zCnName); + pCol->hName = sqlite3StrIHash(pCol->zCnName); + } + assert( IsOrdinaryTable(pNew) ); + pNew->u.tab.pDfltList = sqlite3ExprListDup(db, pTab->u.tab.pDfltList, 0); + pNew->pSchema = db->aDb[iDb].pSchema; + pNew->u.tab.addColOffset = pTab->u.tab.addColOffset; + assert( pNew->nTabRef==1 ); + +exit_begin_add_column: + sqlite3SrcListDelete(db, pSrc); + return; +} + +/* +** Parameter pTab is the subject of an ALTER TABLE ... RENAME COLUMN +** command. This function checks if the table is a view or virtual +** table (columns of views or virtual tables may not be renamed). If so, +** it loads an error message into pParse and returns non-zero. +** +** Or, if pTab is not a view or virtual table, zero is returned. +*/ +#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) +static int isRealTable(Parse *pParse, Table *pTab, int bDrop){ + const char *zType = 0; +#ifndef SQLITE_OMIT_VIEW + if( IsView(pTab) ){ + zType = "view"; + } +#endif +#ifndef SQLITE_OMIT_VIRTUALTABLE + if( IsVirtual(pTab) ){ + zType = "virtual table"; + } +#endif + if( zType ){ + sqlite3ErrorMsg(pParse, "cannot %s %s \"%s\"", + (bDrop ? "drop column from" : "rename columns of"), + zType, pTab->zName + ); + return 1; + } + return 0; +} +#else /* !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) */ +# define isRealTable(x,y,z) (0) +#endif + +/* +** Handles the following parser reduction: +** +** cmd ::= ALTER TABLE pSrc RENAME COLUMN pOld TO pNew +*/ +void sqlite3AlterRenameColumn( + Parse *pParse, /* Parsing context */ + SrcList *pSrc, /* Table being altered. pSrc->nSrc==1 */ + Token *pOld, /* Name of column being changed */ + Token *pNew /* New column name */ +){ + sqlite3 *db = pParse->db; /* Database connection */ + Table *pTab; /* Table being updated */ + int iCol; /* Index of column being renamed */ + char *zOld = 0; /* Old column name */ + char *zNew = 0; /* New column name */ + const char *zDb; /* Name of schema containing the table */ + int iSchema; /* Index of the schema */ + int bQuote; /* True to quote the new name */ + + /* Locate the table to be altered */ + pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]); + if( !pTab ) goto exit_rename_column; + + /* Cannot alter a system table */ + if( SQLITE_OK!=isAlterableTable(pParse, pTab) ) goto exit_rename_column; + if( SQLITE_OK!=isRealTable(pParse, pTab, 0) ) goto exit_rename_column; + + /* Which schema holds the table to be altered */ + iSchema = sqlite3SchemaToIndex(db, pTab->pSchema); + assert( iSchema>=0 ); + zDb = db->aDb[iSchema].zDbSName; + +#ifndef SQLITE_OMIT_AUTHORIZATION + /* Invoke the authorization callback. */ + if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){ + goto exit_rename_column; + } +#endif + + /* Make sure the old name really is a column name in the table to be + ** altered. Set iCol to be the index of the column being renamed */ + zOld = sqlite3NameFromToken(db, pOld); + if( !zOld ) goto exit_rename_column; + for(iCol=0; iCol<pTab->nCol; iCol++){ + if( 0==sqlite3StrICmp(pTab->aCol[iCol].zCnName, zOld) ) break; + } + if( iCol==pTab->nCol ){ + sqlite3ErrorMsg(pParse, "no such column: \"%T\"", pOld); + goto exit_rename_column; + } + + /* Ensure the schema contains no double-quoted strings */ + renameTestSchema(pParse, zDb, iSchema==1, "", 0); + renameFixQuotes(pParse, zDb, iSchema==1); + + /* Do the rename operation using a recursive UPDATE statement that + ** uses the sqlite_rename_column() SQL function to compute the new + ** CREATE statement text for the sqlite_schema table. + */ + sqlite3MayAbort(pParse); + zNew = sqlite3NameFromToken(db, pNew); + if( !zNew ) goto exit_rename_column; + assert( pNew->n>0 ); + bQuote = sqlite3Isquote(pNew->z[0]); + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." LEGACY_SCHEMA_TABLE " SET " + "sql = sqlite_rename_column(sql, type, name, %Q, %Q, %d, %Q, %d, %d) " + "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X' " + " AND (type != 'index' OR tbl_name = %Q)", + zDb, + zDb, pTab->zName, iCol, zNew, bQuote, iSchema==1, + pTab->zName + ); + + sqlite3NestedParse(pParse, + "UPDATE temp." LEGACY_SCHEMA_TABLE " SET " + "sql = sqlite_rename_column(sql, type, name, %Q, %Q, %d, %Q, %d, 1) " + "WHERE type IN ('trigger', 'view')", + zDb, pTab->zName, iCol, zNew, bQuote + ); + + /* Drop and reload the database schema. */ + renameReloadSchema(pParse, iSchema, INITFLAG_AlterRename); + renameTestSchema(pParse, zDb, iSchema==1, "after rename", 1); + + exit_rename_column: + sqlite3SrcListDelete(db, pSrc); + sqlite3DbFree(db, zOld); + sqlite3DbFree(db, zNew); + return; +} + +/* +** Each RenameToken object maps an element of the parse tree into +** the token that generated that element. The parse tree element +** might be one of: +** +** * A pointer to an Expr that represents an ID +** * The name of a table column in Column.zName +** +** A list of RenameToken objects can be constructed during parsing. +** Each new object is created by sqlite3RenameTokenMap(). +** As the parse tree is transformed, the sqlite3RenameTokenRemap() +** routine is used to keep the mapping current. +** +** After the parse finishes, renameTokenFind() routine can be used +** to look up the actual token value that created some element in +** the parse tree. +*/ +struct RenameToken { + const void *p; /* Parse tree element created by token t */ + Token t; /* The token that created parse tree element p */ + RenameToken *pNext; /* Next is a list of all RenameToken objects */ +}; + +/* +** The context of an ALTER TABLE RENAME COLUMN operation that gets passed +** down into the Walker. +*/ +typedef struct RenameCtx RenameCtx; +struct RenameCtx { + RenameToken *pList; /* List of tokens to overwrite */ + int nList; /* Number of tokens in pList */ + int iCol; /* Index of column being renamed */ + Table *pTab; /* Table being ALTERed */ + const char *zOld; /* Old column name */ +}; + +#ifdef SQLITE_DEBUG +/* +** This function is only for debugging. It performs two tasks: +** +** 1. Checks that pointer pPtr does not already appear in the +** rename-token list. +** +** 2. Dereferences each pointer in the rename-token list. +** +** The second is most effective when debugging under valgrind or +** address-sanitizer or similar. If any of these pointers no longer +** point to valid objects, an exception is raised by the memory-checking +** tool. +** +** The point of this is to prevent comparisons of invalid pointer values. +** Even though this always seems to work, it is undefined according to the +** C standard. Example of undefined comparison: +** +** sqlite3_free(x); +** if( x==y ) ... +** +** Technically, as x no longer points into a valid object or to the byte +** following a valid object, it may not be used in comparison operations. +*/ +static void renameTokenCheckAll(Parse *pParse, const void *pPtr){ + assert( pParse==pParse->db->pParse ); + assert( pParse->db->mallocFailed==0 || pParse->nErr!=0 ); + if( pParse->nErr==0 ){ + const RenameToken *p; + u32 i = 1; + for(p=pParse->pRename; p; p=p->pNext){ + if( p->p ){ + assert( p->p!=pPtr ); + i += *(u8*)(p->p) | 1; + } + } + assert( i>0 ); + } +} +#else +# define renameTokenCheckAll(x,y) +#endif + +/* +** Remember that the parser tree element pPtr was created using +** the token pToken. +** +** In other words, construct a new RenameToken object and add it +** to the list of RenameToken objects currently being built up +** in pParse->pRename. +** +** The pPtr argument is returned so that this routine can be used +** with tail recursion in tokenExpr() routine, for a small performance +** improvement. +*/ +const void *sqlite3RenameTokenMap( + Parse *pParse, + const void *pPtr, + const Token *pToken +){ + RenameToken *pNew; + assert( pPtr || pParse->db->mallocFailed ); + renameTokenCheckAll(pParse, pPtr); + if( ALWAYS(pParse->eParseMode!=PARSE_MODE_UNMAP) ){ + pNew = sqlite3DbMallocZero(pParse->db, sizeof(RenameToken)); + if( pNew ){ + pNew->p = pPtr; + pNew->t = *pToken; + pNew->pNext = pParse->pRename; + pParse->pRename = pNew; + } + } + + return pPtr; +} + +/* +** It is assumed that there is already a RenameToken object associated +** with parse tree element pFrom. This function remaps the associated token +** to parse tree element pTo. +*/ +void sqlite3RenameTokenRemap(Parse *pParse, const void *pTo, const void *pFrom){ + RenameToken *p; + renameTokenCheckAll(pParse, pTo); + for(p=pParse->pRename; p; p=p->pNext){ + if( p->p==pFrom ){ + p->p = pTo; + break; + } + } +} + +/* +** Walker callback used by sqlite3RenameExprUnmap(). +*/ +static int renameUnmapExprCb(Walker *pWalker, Expr *pExpr){ + Parse *pParse = pWalker->pParse; + sqlite3RenameTokenRemap(pParse, 0, (const void*)pExpr); + if( ExprUseYTab(pExpr) ){ + sqlite3RenameTokenRemap(pParse, 0, (const void*)&pExpr->y.pTab); + } + return WRC_Continue; +} + +/* +** Iterate through the Select objects that are part of WITH clauses attached +** to select statement pSelect. +*/ +static void renameWalkWith(Walker *pWalker, Select *pSelect){ + With *pWith = pSelect->pWith; + if( pWith ){ + Parse *pParse = pWalker->pParse; + int i; + With *pCopy = 0; + assert( pWith->nCte>0 ); + if( (pWith->a[0].pSelect->selFlags & SF_Expanded)==0 ){ + /* Push a copy of the With object onto the with-stack. We use a copy + ** here as the original will be expanded and resolved (flags SF_Expanded + ** and SF_Resolved) below. And the parser code that uses the with-stack + ** fails if the Select objects on it have already been expanded and + ** resolved. */ + pCopy = sqlite3WithDup(pParse->db, pWith); + pCopy = sqlite3WithPush(pParse, pCopy, 1); + } + for(i=0; i<pWith->nCte; i++){ + Select *p = pWith->a[i].pSelect; + NameContext sNC; + memset(&sNC, 0, sizeof(sNC)); + sNC.pParse = pParse; + if( pCopy ) sqlite3SelectPrep(sNC.pParse, p, &sNC); + if( sNC.pParse->db->mallocFailed ) return; + sqlite3WalkSelect(pWalker, p); + sqlite3RenameExprlistUnmap(pParse, pWith->a[i].pCols); + } + if( pCopy && pParse->pWith==pCopy ){ + pParse->pWith = pCopy->pOuter; + } + } +} + +/* +** Unmap all tokens in the IdList object passed as the second argument. +*/ +static void unmapColumnIdlistNames( + Parse *pParse, + const IdList *pIdList +){ + int ii; + assert( pIdList!=0 ); + for(ii=0; ii<pIdList->nId; ii++){ + sqlite3RenameTokenRemap(pParse, 0, (const void*)pIdList->a[ii].zName); + } +} + +/* +** Walker callback used by sqlite3RenameExprUnmap(). +*/ +static int renameUnmapSelectCb(Walker *pWalker, Select *p){ + Parse *pParse = pWalker->pParse; + int i; + if( pParse->nErr ) return WRC_Abort; + testcase( p->selFlags & SF_View ); + testcase( p->selFlags & SF_CopyCte ); + if( p->selFlags & (SF_View|SF_CopyCte) ){ + return WRC_Prune; + } + if( ALWAYS(p->pEList) ){ + ExprList *pList = p->pEList; + for(i=0; i<pList->nExpr; i++){ + if( pList->a[i].zEName && pList->a[i].fg.eEName==ENAME_NAME ){ + sqlite3RenameTokenRemap(pParse, 0, (void*)pList->a[i].zEName); + } + } + } + if( ALWAYS(p->pSrc) ){ /* Every Select as a SrcList, even if it is empty */ + SrcList *pSrc = p->pSrc; + for(i=0; i<pSrc->nSrc; i++){ + sqlite3RenameTokenRemap(pParse, 0, (void*)pSrc->a[i].zName); + if( pSrc->a[i].fg.isUsing==0 ){ + sqlite3WalkExpr(pWalker, pSrc->a[i].u3.pOn); + }else{ + unmapColumnIdlistNames(pParse, pSrc->a[i].u3.pUsing); + } + } + } + + renameWalkWith(pWalker, p); + return WRC_Continue; +} + +/* +** Remove all nodes that are part of expression pExpr from the rename list. +*/ +void sqlite3RenameExprUnmap(Parse *pParse, Expr *pExpr){ + u8 eMode = pParse->eParseMode; + Walker sWalker; + memset(&sWalker, 0, sizeof(Walker)); + sWalker.pParse = pParse; + sWalker.xExprCallback = renameUnmapExprCb; + sWalker.xSelectCallback = renameUnmapSelectCb; + pParse->eParseMode = PARSE_MODE_UNMAP; + sqlite3WalkExpr(&sWalker, pExpr); + pParse->eParseMode = eMode; +} + +/* +** Remove all nodes that are part of expression-list pEList from the +** rename list. +*/ +void sqlite3RenameExprlistUnmap(Parse *pParse, ExprList *pEList){ + if( pEList ){ + int i; + Walker sWalker; + memset(&sWalker, 0, sizeof(Walker)); + sWalker.pParse = pParse; + sWalker.xExprCallback = renameUnmapExprCb; + sqlite3WalkExprList(&sWalker, pEList); + for(i=0; i<pEList->nExpr; i++){ + if( ALWAYS(pEList->a[i].fg.eEName==ENAME_NAME) ){ + sqlite3RenameTokenRemap(pParse, 0, (void*)pEList->a[i].zEName); + } + } + } +} + +/* +** Free the list of RenameToken objects given in the second argument +*/ +static void renameTokenFree(sqlite3 *db, RenameToken *pToken){ + RenameToken *pNext; + RenameToken *p; + for(p=pToken; p; p=pNext){ + pNext = p->pNext; + sqlite3DbFree(db, p); + } +} + +/* +** Search the Parse object passed as the first argument for a RenameToken +** object associated with parse tree element pPtr. If found, return a pointer +** to it. Otherwise, return NULL. +** +** If the second argument passed to this function is not NULL and a matching +** RenameToken object is found, remove it from the Parse object and add it to +** the list maintained by the RenameCtx object. +*/ +static RenameToken *renameTokenFind( + Parse *pParse, + struct RenameCtx *pCtx, + const void *pPtr +){ + RenameToken **pp; + if( NEVER(pPtr==0) ){ + return 0; + } + for(pp=&pParse->pRename; (*pp); pp=&(*pp)->pNext){ + if( (*pp)->p==pPtr ){ + RenameToken *pToken = *pp; + if( pCtx ){ + *pp = pToken->pNext; + pToken->pNext = pCtx->pList; + pCtx->pList = pToken; + pCtx->nList++; + } + return pToken; + } + } + return 0; +} + +/* +** This is a Walker select callback. It does nothing. It is only required +** because without a dummy callback, sqlite3WalkExpr() and similar do not +** descend into sub-select statements. +*/ +static int renameColumnSelectCb(Walker *pWalker, Select *p){ + if( p->selFlags & (SF_View|SF_CopyCte) ){ + testcase( p->selFlags & SF_View ); + testcase( p->selFlags & SF_CopyCte ); + return WRC_Prune; + } + renameWalkWith(pWalker, p); + return WRC_Continue; +} + +/* +** This is a Walker expression callback. +** +** For every TK_COLUMN node in the expression tree, search to see +** if the column being references is the column being renamed by an +** ALTER TABLE statement. If it is, then attach its associated +** RenameToken object to the list of RenameToken objects being +** constructed in RenameCtx object at pWalker->u.pRename. +*/ +static int renameColumnExprCb(Walker *pWalker, Expr *pExpr){ + RenameCtx *p = pWalker->u.pRename; + if( pExpr->op==TK_TRIGGER + && pExpr->iColumn==p->iCol + && pWalker->pParse->pTriggerTab==p->pTab + ){ + renameTokenFind(pWalker->pParse, p, (void*)pExpr); + }else if( pExpr->op==TK_COLUMN + && pExpr->iColumn==p->iCol + && ALWAYS(ExprUseYTab(pExpr)) + && p->pTab==pExpr->y.pTab + ){ + renameTokenFind(pWalker->pParse, p, (void*)pExpr); + } + return WRC_Continue; +} + +/* +** The RenameCtx contains a list of tokens that reference a column that +** is being renamed by an ALTER TABLE statement. Return the "last" +** RenameToken in the RenameCtx and remove that RenameToken from the +** RenameContext. "Last" means the last RenameToken encountered when +** the input SQL is parsed from left to right. Repeated calls to this routine +** return all column name tokens in the order that they are encountered +** in the SQL statement. +*/ +static RenameToken *renameColumnTokenNext(RenameCtx *pCtx){ + RenameToken *pBest = pCtx->pList; + RenameToken *pToken; + RenameToken **pp; + + for(pToken=pBest->pNext; pToken; pToken=pToken->pNext){ + if( pToken->t.z>pBest->t.z ) pBest = pToken; + } + for(pp=&pCtx->pList; *pp!=pBest; pp=&(*pp)->pNext); + *pp = pBest->pNext; + + return pBest; +} + +/* +** An error occurred while parsing or otherwise processing a database +** object (either pParse->pNewTable, pNewIndex or pNewTrigger) as part of an +** ALTER TABLE RENAME COLUMN program. The error message emitted by the +** sub-routine is currently stored in pParse->zErrMsg. This function +** adds context to the error message and then stores it in pCtx. +*/ +static void renameColumnParseError( + sqlite3_context *pCtx, + const char *zWhen, + sqlite3_value *pType, + sqlite3_value *pObject, + Parse *pParse +){ + const char *zT = (const char*)sqlite3_value_text(pType); + const char *zN = (const char*)sqlite3_value_text(pObject); + char *zErr; + + zErr = sqlite3MPrintf(pParse->db, "error in %s %s%s%s: %s", + zT, zN, (zWhen[0] ? " " : ""), zWhen, + pParse->zErrMsg + ); + sqlite3_result_error(pCtx, zErr, -1); + sqlite3DbFree(pParse->db, zErr); +} + +/* +** For each name in the the expression-list pEList (i.e. each +** pEList->a[i].zName) that matches the string in zOld, extract the +** corresponding rename-token from Parse object pParse and add it +** to the RenameCtx pCtx. +*/ +static void renameColumnElistNames( + Parse *pParse, + RenameCtx *pCtx, + const ExprList *pEList, + const char *zOld +){ + if( pEList ){ + int i; + for(i=0; i<pEList->nExpr; i++){ + const char *zName = pEList->a[i].zEName; + if( ALWAYS(pEList->a[i].fg.eEName==ENAME_NAME) + && ALWAYS(zName!=0) + && 0==sqlite3_stricmp(zName, zOld) + ){ + renameTokenFind(pParse, pCtx, (const void*)zName); + } + } + } +} + +/* +** For each name in the the id-list pIdList (i.e. each pIdList->a[i].zName) +** that matches the string in zOld, extract the corresponding rename-token +** from Parse object pParse and add it to the RenameCtx pCtx. +*/ +static void renameColumnIdlistNames( + Parse *pParse, + RenameCtx *pCtx, + const IdList *pIdList, + const char *zOld +){ + if( pIdList ){ + int i; + for(i=0; i<pIdList->nId; i++){ + const char *zName = pIdList->a[i].zName; + if( 0==sqlite3_stricmp(zName, zOld) ){ + renameTokenFind(pParse, pCtx, (const void*)zName); + } + } + } +} + + +/* +** Parse the SQL statement zSql using Parse object (*p). The Parse object +** is initialized by this function before it is used. +*/ +static int renameParseSql( + Parse *p, /* Memory to use for Parse object */ + const char *zDb, /* Name of schema SQL belongs to */ + sqlite3 *db, /* Database handle */ + const char *zSql, /* SQL to parse */ + int bTemp /* True if SQL is from temp schema */ +){ + int rc; + + sqlite3ParseObjectInit(p, db); + if( zSql==0 ){ + return SQLITE_NOMEM; + } + if( sqlite3StrNICmp(zSql,"CREATE ",7)!=0 ){ + return SQLITE_CORRUPT_BKPT; + } + db->init.iDb = bTemp ? 1 : sqlite3FindDbName(db, zDb); + p->eParseMode = PARSE_MODE_RENAME; + p->db = db; + p->nQueryLoop = 1; + rc = sqlite3RunParser(p, zSql); + if( db->mallocFailed ) rc = SQLITE_NOMEM; + if( rc==SQLITE_OK + && NEVER(p->pNewTable==0 && p->pNewIndex==0 && p->pNewTrigger==0) + ){ + rc = SQLITE_CORRUPT_BKPT; + } + +#ifdef SQLITE_DEBUG + /* Ensure that all mappings in the Parse.pRename list really do map to + ** a part of the input string. */ + if( rc==SQLITE_OK ){ + int nSql = sqlite3Strlen30(zSql); + RenameToken *pToken; + for(pToken=p->pRename; pToken; pToken=pToken->pNext){ + assert( pToken->t.z>=zSql && &pToken->t.z[pToken->t.n]<=&zSql[nSql] ); + } + } +#endif + + db->init.iDb = 0; + return rc; +} + +/* +** This function edits SQL statement zSql, replacing each token identified +** by the linked list pRename with the text of zNew. If argument bQuote is +** true, then zNew is always quoted first. If no error occurs, the result +** is loaded into context object pCtx as the result. +** +** Or, if an error occurs (i.e. an OOM condition), an error is left in +** pCtx and an SQLite error code returned. +*/ +static int renameEditSql( + sqlite3_context *pCtx, /* Return result here */ + RenameCtx *pRename, /* Rename context */ + const char *zSql, /* SQL statement to edit */ + const char *zNew, /* New token text */ + int bQuote /* True to always quote token */ +){ + i64 nNew = sqlite3Strlen30(zNew); + i64 nSql = sqlite3Strlen30(zSql); + sqlite3 *db = sqlite3_context_db_handle(pCtx); + int rc = SQLITE_OK; + char *zQuot = 0; + char *zOut; + i64 nQuot = 0; + char *zBuf1 = 0; + char *zBuf2 = 0; + + if( zNew ){ + /* Set zQuot to point to a buffer containing a quoted copy of the + ** identifier zNew. If the corresponding identifier in the original + ** ALTER TABLE statement was quoted (bQuote==1), then set zNew to + ** point to zQuot so that all substitutions are made using the + ** quoted version of the new column name. */ + zQuot = sqlite3MPrintf(db, "\"%w\" ", zNew); + if( zQuot==0 ){ + return SQLITE_NOMEM; + }else{ + nQuot = sqlite3Strlen30(zQuot)-1; + } + + assert( nQuot>=nNew ); + zOut = sqlite3DbMallocZero(db, nSql + pRename->nList*nQuot + 1); + }else{ + zOut = (char*)sqlite3DbMallocZero(db, (nSql*2+1) * 3); + if( zOut ){ + zBuf1 = &zOut[nSql*2+1]; + zBuf2 = &zOut[nSql*4+2]; + } + } + + /* At this point pRename->pList contains a list of RenameToken objects + ** corresponding to all tokens in the input SQL that must be replaced + ** with the new column name, or with single-quoted versions of themselves. + ** All that remains is to construct and return the edited SQL string. */ + if( zOut ){ + int nOut = nSql; + memcpy(zOut, zSql, nSql); + while( pRename->pList ){ + int iOff; /* Offset of token to replace in zOut */ + u32 nReplace; + const char *zReplace; + RenameToken *pBest = renameColumnTokenNext(pRename); + + if( zNew ){ + if( bQuote==0 && sqlite3IsIdChar(*pBest->t.z) ){ + nReplace = nNew; + zReplace = zNew; + }else{ + nReplace = nQuot; + zReplace = zQuot; + if( pBest->t.z[pBest->t.n]=='"' ) nReplace++; + } + }else{ + /* Dequote the double-quoted token. Then requote it again, this time + ** using single quotes. If the character immediately following the + ** original token within the input SQL was a single quote ('), then + ** add another space after the new, single-quoted version of the + ** token. This is so that (SELECT "string"'alias') maps to + ** (SELECT 'string' 'alias'), and not (SELECT 'string''alias'). */ + memcpy(zBuf1, pBest->t.z, pBest->t.n); + zBuf1[pBest->t.n] = 0; + sqlite3Dequote(zBuf1); + sqlite3_snprintf(nSql*2, zBuf2, "%Q%s", zBuf1, + pBest->t.z[pBest->t.n]=='\'' ? " " : "" + ); + zReplace = zBuf2; + nReplace = sqlite3Strlen30(zReplace); + } + + iOff = pBest->t.z - zSql; + if( pBest->t.n!=nReplace ){ + memmove(&zOut[iOff + nReplace], &zOut[iOff + pBest->t.n], + nOut - (iOff + pBest->t.n) + ); + nOut += nReplace - pBest->t.n; + zOut[nOut] = '\0'; + } + memcpy(&zOut[iOff], zReplace, nReplace); + sqlite3DbFree(db, pBest); + } + + sqlite3_result_text(pCtx, zOut, -1, SQLITE_TRANSIENT); + sqlite3DbFree(db, zOut); + }else{ + rc = SQLITE_NOMEM; + } + + sqlite3_free(zQuot); + return rc; +} + +/* +** Set all pEList->a[].fg.eEName fields in the expression-list to val. +*/ +static void renameSetENames(ExprList *pEList, int val){ + if( pEList ){ + int i; + for(i=0; i<pEList->nExpr; i++){ + assert( val==ENAME_NAME || pEList->a[i].fg.eEName==ENAME_NAME ); + pEList->a[i].fg.eEName = val; + } + } +} + +/* +** Resolve all symbols in the trigger at pParse->pNewTrigger, assuming +** it was read from the schema of database zDb. Return SQLITE_OK if +** successful. Otherwise, return an SQLite error code and leave an error +** message in the Parse object. +*/ +static int renameResolveTrigger(Parse *pParse){ + sqlite3 *db = pParse->db; + Trigger *pNew = pParse->pNewTrigger; + TriggerStep *pStep; + NameContext sNC; + int rc = SQLITE_OK; + + memset(&sNC, 0, sizeof(sNC)); + sNC.pParse = pParse; + assert( pNew->pTabSchema ); + pParse->pTriggerTab = sqlite3FindTable(db, pNew->table, + db->aDb[sqlite3SchemaToIndex(db, pNew->pTabSchema)].zDbSName + ); + pParse->eTriggerOp = pNew->op; + /* ALWAYS() because if the table of the trigger does not exist, the + ** error would have been hit before this point */ + if( ALWAYS(pParse->pTriggerTab) ){ + rc = sqlite3ViewGetColumnNames(pParse, pParse->pTriggerTab); + } + + /* Resolve symbols in WHEN clause */ + if( rc==SQLITE_OK && pNew->pWhen ){ + rc = sqlite3ResolveExprNames(&sNC, pNew->pWhen); + } + + for(pStep=pNew->step_list; rc==SQLITE_OK && pStep; pStep=pStep->pNext){ + if( pStep->pSelect ){ + sqlite3SelectPrep(pParse, pStep->pSelect, &sNC); + if( pParse->nErr ) rc = pParse->rc; + } + if( rc==SQLITE_OK && pStep->zTarget ){ + SrcList *pSrc = sqlite3TriggerStepSrc(pParse, pStep); + if( pSrc ){ + Select *pSel = sqlite3SelectNew( + pParse, pStep->pExprList, pSrc, 0, 0, 0, 0, 0, 0 + ); + if( pSel==0 ){ + pStep->pExprList = 0; + pSrc = 0; + rc = SQLITE_NOMEM; + }else{ + /* pStep->pExprList contains an expression-list used for an UPDATE + ** statement. So the a[].zEName values are the RHS of the + ** "<col> = <expr>" clauses of the UPDATE statement. So, before + ** running SelectPrep(), change all the eEName values in + ** pStep->pExprList to ENAME_SPAN (from their current value of + ** ENAME_NAME). This is to prevent any ids in ON() clauses that are + ** part of pSrc from being incorrectly resolved against the + ** a[].zEName values as if they were column aliases. */ + renameSetENames(pStep->pExprList, ENAME_SPAN); + sqlite3SelectPrep(pParse, pSel, 0); + renameSetENames(pStep->pExprList, ENAME_NAME); + rc = pParse->nErr ? SQLITE_ERROR : SQLITE_OK; + assert( pStep->pExprList==0 || pStep->pExprList==pSel->pEList ); + assert( pSrc==pSel->pSrc ); + if( pStep->pExprList ) pSel->pEList = 0; + pSel->pSrc = 0; + sqlite3SelectDelete(db, pSel); + } + if( pStep->pFrom ){ + int i; + for(i=0; i<pStep->pFrom->nSrc && rc==SQLITE_OK; i++){ + SrcItem *p = &pStep->pFrom->a[i]; + if( p->pSelect ){ + sqlite3SelectPrep(pParse, p->pSelect, 0); + } + } + } + + if( db->mallocFailed ){ + rc = SQLITE_NOMEM; + } + sNC.pSrcList = pSrc; + if( rc==SQLITE_OK && pStep->pWhere ){ + rc = sqlite3ResolveExprNames(&sNC, pStep->pWhere); + } + if( rc==SQLITE_OK ){ + rc = sqlite3ResolveExprListNames(&sNC, pStep->pExprList); + } + assert( !pStep->pUpsert || (!pStep->pWhere && !pStep->pExprList) ); + if( pStep->pUpsert && rc==SQLITE_OK ){ + Upsert *pUpsert = pStep->pUpsert; + pUpsert->pUpsertSrc = pSrc; + sNC.uNC.pUpsert = pUpsert; + sNC.ncFlags = NC_UUpsert; + rc = sqlite3ResolveExprListNames(&sNC, pUpsert->pUpsertTarget); + if( rc==SQLITE_OK ){ + ExprList *pUpsertSet = pUpsert->pUpsertSet; + rc = sqlite3ResolveExprListNames(&sNC, pUpsertSet); + } + if( rc==SQLITE_OK ){ + rc = sqlite3ResolveExprNames(&sNC, pUpsert->pUpsertWhere); + } + if( rc==SQLITE_OK ){ + rc = sqlite3ResolveExprNames(&sNC, pUpsert->pUpsertTargetWhere); + } + sNC.ncFlags = 0; + } + sNC.pSrcList = 0; + sqlite3SrcListDelete(db, pSrc); + }else{ + rc = SQLITE_NOMEM; + } + } + } + return rc; +} + +/* +** Invoke sqlite3WalkExpr() or sqlite3WalkSelect() on all Select or Expr +** objects that are part of the trigger passed as the second argument. +*/ +static void renameWalkTrigger(Walker *pWalker, Trigger *pTrigger){ + TriggerStep *pStep; + + /* Find tokens to edit in WHEN clause */ + sqlite3WalkExpr(pWalker, pTrigger->pWhen); + + /* Find tokens to edit in trigger steps */ + for(pStep=pTrigger->step_list; pStep; pStep=pStep->pNext){ + sqlite3WalkSelect(pWalker, pStep->pSelect); + sqlite3WalkExpr(pWalker, pStep->pWhere); + sqlite3WalkExprList(pWalker, pStep->pExprList); + if( pStep->pUpsert ){ + Upsert *pUpsert = pStep->pUpsert; + sqlite3WalkExprList(pWalker, pUpsert->pUpsertTarget); + sqlite3WalkExprList(pWalker, pUpsert->pUpsertSet); + sqlite3WalkExpr(pWalker, pUpsert->pUpsertWhere); + sqlite3WalkExpr(pWalker, pUpsert->pUpsertTargetWhere); + } + if( pStep->pFrom ){ + int i; + for(i=0; i<pStep->pFrom->nSrc; i++){ + sqlite3WalkSelect(pWalker, pStep->pFrom->a[i].pSelect); + } + } + } +} + +/* +** Free the contents of Parse object (*pParse). Do not free the memory +** occupied by the Parse object itself. +*/ +static void renameParseCleanup(Parse *pParse){ + sqlite3 *db = pParse->db; + Index *pIdx; + if( pParse->pVdbe ){ + sqlite3VdbeFinalize(pParse->pVdbe); + } + sqlite3DeleteTable(db, pParse->pNewTable); + while( (pIdx = pParse->pNewIndex)!=0 ){ + pParse->pNewIndex = pIdx->pNext; + sqlite3FreeIndex(db, pIdx); + } + sqlite3DeleteTrigger(db, pParse->pNewTrigger); + sqlite3DbFree(db, pParse->zErrMsg); + renameTokenFree(db, pParse->pRename); + sqlite3ParseObjectReset(pParse); +} + +/* +** SQL function: +** +** sqlite_rename_column(SQL,TYPE,OBJ,DB,TABLE,COL,NEWNAME,QUOTE,TEMP) +** +** 0. zSql: SQL statement to rewrite +** 1. type: Type of object ("table", "view" etc.) +** 2. object: Name of object +** 3. Database: Database name (e.g. "main") +** 4. Table: Table name +** 5. iCol: Index of column to rename +** 6. zNew: New column name +** 7. bQuote: Non-zero if the new column name should be quoted. +** 8. bTemp: True if zSql comes from temp schema +** +** Do a column rename operation on the CREATE statement given in zSql. +** The iCol-th column (left-most is 0) of table zTable is renamed from zCol +** into zNew. The name should be quoted if bQuote is true. +** +** This function is used internally by the ALTER TABLE RENAME COLUMN command. +** It is only accessible to SQL created using sqlite3NestedParse(). It is +** not reachable from ordinary SQL passed into sqlite3_prepare() unless the +** SQLITE_TESTCTRL_INTERNAL_FUNCTIONS test setting is enabled. +*/ +static void renameColumnFunc( + sqlite3_context *context, + int NotUsed, + sqlite3_value **argv +){ + sqlite3 *db = sqlite3_context_db_handle(context); + RenameCtx sCtx; + const char *zSql = (const char*)sqlite3_value_text(argv[0]); + const char *zDb = (const char*)sqlite3_value_text(argv[3]); + const char *zTable = (const char*)sqlite3_value_text(argv[4]); + int iCol = sqlite3_value_int(argv[5]); + const char *zNew = (const char*)sqlite3_value_text(argv[6]); + int bQuote = sqlite3_value_int(argv[7]); + int bTemp = sqlite3_value_int(argv[8]); + const char *zOld; + int rc; + Parse sParse; + Walker sWalker; + Index *pIdx; + int i; + Table *pTab; +#ifndef SQLITE_OMIT_AUTHORIZATION + sqlite3_xauth xAuth = db->xAuth; +#endif + + UNUSED_PARAMETER(NotUsed); + if( zSql==0 ) return; + if( zTable==0 ) return; + if( zNew==0 ) return; + if( iCol<0 ) return; + sqlite3BtreeEnterAll(db); + pTab = sqlite3FindTable(db, zTable, zDb); + if( pTab==0 || iCol>=pTab->nCol ){ + sqlite3BtreeLeaveAll(db); + return; + } + zOld = pTab->aCol[iCol].zCnName; + memset(&sCtx, 0, sizeof(sCtx)); + sCtx.iCol = ((iCol==pTab->iPKey) ? -1 : iCol); + +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = 0; +#endif + rc = renameParseSql(&sParse, zDb, db, zSql, bTemp); + + /* Find tokens that need to be replaced. */ + memset(&sWalker, 0, sizeof(Walker)); + sWalker.pParse = &sParse; + sWalker.xExprCallback = renameColumnExprCb; + sWalker.xSelectCallback = renameColumnSelectCb; + sWalker.u.pRename = &sCtx; + + sCtx.pTab = pTab; + if( rc!=SQLITE_OK ) goto renameColumnFunc_done; + if( sParse.pNewTable ){ + if( IsView(sParse.pNewTable) ){ + Select *pSelect = sParse.pNewTable->u.view.pSelect; + pSelect->selFlags &= ~SF_View; + sParse.rc = SQLITE_OK; + sqlite3SelectPrep(&sParse, pSelect, 0); + rc = (db->mallocFailed ? SQLITE_NOMEM : sParse.rc); + if( rc==SQLITE_OK ){ + sqlite3WalkSelect(&sWalker, pSelect); + } + if( rc!=SQLITE_OK ) goto renameColumnFunc_done; + }else if( IsOrdinaryTable(sParse.pNewTable) ){ + /* A regular table */ + int bFKOnly = sqlite3_stricmp(zTable, sParse.pNewTable->zName); + FKey *pFKey; + sCtx.pTab = sParse.pNewTable; + if( bFKOnly==0 ){ + if( iCol<sParse.pNewTable->nCol ){ + renameTokenFind( + &sParse, &sCtx, (void*)sParse.pNewTable->aCol[iCol].zCnName + ); + } + if( sCtx.iCol<0 ){ + renameTokenFind(&sParse, &sCtx, (void*)&sParse.pNewTable->iPKey); + } + sqlite3WalkExprList(&sWalker, sParse.pNewTable->pCheck); + for(pIdx=sParse.pNewTable->pIndex; pIdx; pIdx=pIdx->pNext){ + sqlite3WalkExprList(&sWalker, pIdx->aColExpr); + } + for(pIdx=sParse.pNewIndex; pIdx; pIdx=pIdx->pNext){ + sqlite3WalkExprList(&sWalker, pIdx->aColExpr); + } +#ifndef SQLITE_OMIT_GENERATED_COLUMNS + for(i=0; i<sParse.pNewTable->nCol; i++){ + Expr *pExpr = sqlite3ColumnExpr(sParse.pNewTable, + &sParse.pNewTable->aCol[i]); + sqlite3WalkExpr(&sWalker, pExpr); + } +#endif + } + + assert( IsOrdinaryTable(sParse.pNewTable) ); + for(pFKey=sParse.pNewTable->u.tab.pFKey; pFKey; pFKey=pFKey->pNextFrom){ + for(i=0; i<pFKey->nCol; i++){ + if( bFKOnly==0 && pFKey->aCol[i].iFrom==iCol ){ + renameTokenFind(&sParse, &sCtx, (void*)&pFKey->aCol[i]); + } + if( 0==sqlite3_stricmp(pFKey->zTo, zTable) + && 0==sqlite3_stricmp(pFKey->aCol[i].zCol, zOld) + ){ + renameTokenFind(&sParse, &sCtx, (void*)pFKey->aCol[i].zCol); + } + } + } + } + }else if( sParse.pNewIndex ){ + sqlite3WalkExprList(&sWalker, sParse.pNewIndex->aColExpr); + sqlite3WalkExpr(&sWalker, sParse.pNewIndex->pPartIdxWhere); + }else{ + /* A trigger */ + TriggerStep *pStep; + rc = renameResolveTrigger(&sParse); + if( rc!=SQLITE_OK ) goto renameColumnFunc_done; + + for(pStep=sParse.pNewTrigger->step_list; pStep; pStep=pStep->pNext){ + if( pStep->zTarget ){ + Table *pTarget = sqlite3LocateTable(&sParse, 0, pStep->zTarget, zDb); + if( pTarget==pTab ){ + if( pStep->pUpsert ){ + ExprList *pUpsertSet = pStep->pUpsert->pUpsertSet; + renameColumnElistNames(&sParse, &sCtx, pUpsertSet, zOld); + } + renameColumnIdlistNames(&sParse, &sCtx, pStep->pIdList, zOld); + renameColumnElistNames(&sParse, &sCtx, pStep->pExprList, zOld); + } + } + } + + + /* Find tokens to edit in UPDATE OF clause */ + if( sParse.pTriggerTab==pTab ){ + renameColumnIdlistNames(&sParse, &sCtx,sParse.pNewTrigger->pColumns,zOld); + } + + /* Find tokens to edit in various expressions and selects */ + renameWalkTrigger(&sWalker, sParse.pNewTrigger); + } + + assert( rc==SQLITE_OK ); + rc = renameEditSql(context, &sCtx, zSql, zNew, bQuote); + +renameColumnFunc_done: + if( rc!=SQLITE_OK ){ + if( rc==SQLITE_ERROR && sqlite3WritableSchema(db) ){ + sqlite3_result_value(context, argv[0]); + }else if( sParse.zErrMsg ){ + renameColumnParseError(context, "", argv[1], argv[2], &sParse); + }else{ + sqlite3_result_error_code(context, rc); + } + } + + renameParseCleanup(&sParse); + renameTokenFree(db, sCtx.pList); +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = xAuth; +#endif + sqlite3BtreeLeaveAll(db); +} + +/* +** Walker expression callback used by "RENAME TABLE". +*/ +static int renameTableExprCb(Walker *pWalker, Expr *pExpr){ + RenameCtx *p = pWalker->u.pRename; + if( pExpr->op==TK_COLUMN + && ALWAYS(ExprUseYTab(pExpr)) + && p->pTab==pExpr->y.pTab + ){ + renameTokenFind(pWalker->pParse, p, (void*)&pExpr->y.pTab); + } + return WRC_Continue; +} + +/* +** Walker select callback used by "RENAME TABLE". +*/ +static int renameTableSelectCb(Walker *pWalker, Select *pSelect){ + int i; + RenameCtx *p = pWalker->u.pRename; + SrcList *pSrc = pSelect->pSrc; + if( pSelect->selFlags & (SF_View|SF_CopyCte) ){ + testcase( pSelect->selFlags & SF_View ); + testcase( pSelect->selFlags & SF_CopyCte ); + return WRC_Prune; + } + if( NEVER(pSrc==0) ){ + assert( pWalker->pParse->db->mallocFailed ); + return WRC_Abort; + } + for(i=0; i<pSrc->nSrc; i++){ + SrcItem *pItem = &pSrc->a[i]; + if( pItem->pTab==p->pTab ){ + renameTokenFind(pWalker->pParse, p, pItem->zName); + } + } + renameWalkWith(pWalker, pSelect); + + return WRC_Continue; +} + + +/* +** 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: +** +** 0: The database containing the table being renamed. +** 1. type: Type of object ("table", "view" etc.) +** 2. object: Name of object +** 3: The complete text of the schema statement being modified, +** 4: The old name of the table being renamed, and +** 5: The new name of the table being renamed. +** 6: True if the schema statement comes from the temp db. +** +** It returns the new schema statement. For example: +** +** sqlite_rename_table('main', 'CREATE TABLE t1(a REFERENCES t2)','t2','t3',0) +** -> 'CREATE TABLE t1(a REFERENCES t3)' +*/ +static void renameTableFunc( + sqlite3_context *context, + int NotUsed, + sqlite3_value **argv +){ + sqlite3 *db = sqlite3_context_db_handle(context); + const char *zDb = (const char*)sqlite3_value_text(argv[0]); + const char *zInput = (const char*)sqlite3_value_text(argv[3]); + const char *zOld = (const char*)sqlite3_value_text(argv[4]); + const char *zNew = (const char*)sqlite3_value_text(argv[5]); + int bTemp = sqlite3_value_int(argv[6]); + UNUSED_PARAMETER(NotUsed); + + if( zInput && zOld && zNew ){ + Parse sParse; + int rc; + int bQuote = 1; + RenameCtx sCtx; + Walker sWalker; + +#ifndef SQLITE_OMIT_AUTHORIZATION + sqlite3_xauth xAuth = db->xAuth; + db->xAuth = 0; +#endif + + sqlite3BtreeEnterAll(db); + + memset(&sCtx, 0, sizeof(RenameCtx)); + sCtx.pTab = sqlite3FindTable(db, zOld, zDb); + memset(&sWalker, 0, sizeof(Walker)); + sWalker.pParse = &sParse; + sWalker.xExprCallback = renameTableExprCb; + sWalker.xSelectCallback = renameTableSelectCb; + sWalker.u.pRename = &sCtx; + + rc = renameParseSql(&sParse, zDb, db, zInput, bTemp); + + if( rc==SQLITE_OK ){ + int isLegacy = (db->flags & SQLITE_LegacyAlter); + if( sParse.pNewTable ){ + Table *pTab = sParse.pNewTable; + + if( IsView(pTab) ){ + if( isLegacy==0 ){ + Select *pSelect = pTab->u.view.pSelect; + NameContext sNC; + memset(&sNC, 0, sizeof(sNC)); + sNC.pParse = &sParse; + + assert( pSelect->selFlags & SF_View ); + pSelect->selFlags &= ~SF_View; + sqlite3SelectPrep(&sParse, pTab->u.view.pSelect, &sNC); + if( sParse.nErr ){ + rc = sParse.rc; + }else{ + sqlite3WalkSelect(&sWalker, pTab->u.view.pSelect); + } + } + }else{ + /* Modify any FK definitions to point to the new table. */ +#ifndef SQLITE_OMIT_FOREIGN_KEY + if( (isLegacy==0 || (db->flags & SQLITE_ForeignKeys)) + && !IsVirtual(pTab) + ){ + FKey *pFKey; + assert( IsOrdinaryTable(pTab) ); + for(pFKey=pTab->u.tab.pFKey; pFKey; pFKey=pFKey->pNextFrom){ + if( sqlite3_stricmp(pFKey->zTo, zOld)==0 ){ + renameTokenFind(&sParse, &sCtx, (void*)pFKey->zTo); + } + } + } +#endif + + /* If this is the table being altered, fix any table refs in CHECK + ** expressions. Also update the name that appears right after the + ** "CREATE [VIRTUAL] TABLE" bit. */ + if( sqlite3_stricmp(zOld, pTab->zName)==0 ){ + sCtx.pTab = pTab; + if( isLegacy==0 ){ + sqlite3WalkExprList(&sWalker, pTab->pCheck); + } + renameTokenFind(&sParse, &sCtx, pTab->zName); + } + } + } + + else if( sParse.pNewIndex ){ + renameTokenFind(&sParse, &sCtx, sParse.pNewIndex->zName); + if( isLegacy==0 ){ + sqlite3WalkExpr(&sWalker, sParse.pNewIndex->pPartIdxWhere); + } + } + +#ifndef SQLITE_OMIT_TRIGGER + else{ + Trigger *pTrigger = sParse.pNewTrigger; + TriggerStep *pStep; + if( 0==sqlite3_stricmp(sParse.pNewTrigger->table, zOld) + && sCtx.pTab->pSchema==pTrigger->pTabSchema + ){ + renameTokenFind(&sParse, &sCtx, sParse.pNewTrigger->table); + } + + if( isLegacy==0 ){ + rc = renameResolveTrigger(&sParse); + if( rc==SQLITE_OK ){ + renameWalkTrigger(&sWalker, pTrigger); + for(pStep=pTrigger->step_list; pStep; pStep=pStep->pNext){ + if( pStep->zTarget && 0==sqlite3_stricmp(pStep->zTarget, zOld) ){ + renameTokenFind(&sParse, &sCtx, pStep->zTarget); + } + if( pStep->pFrom ){ + int i; + for(i=0; i<pStep->pFrom->nSrc; i++){ + SrcItem *pItem = &pStep->pFrom->a[i]; + if( 0==sqlite3_stricmp(pItem->zName, zOld) ){ + renameTokenFind(&sParse, &sCtx, pItem->zName); + } + } + } + } + } + } + } +#endif + } + + if( rc==SQLITE_OK ){ + rc = renameEditSql(context, &sCtx, zInput, zNew, bQuote); + } + if( rc!=SQLITE_OK ){ + if( rc==SQLITE_ERROR && sqlite3WritableSchema(db) ){ + sqlite3_result_value(context, argv[3]); + }else if( sParse.zErrMsg ){ + renameColumnParseError(context, "", argv[1], argv[2], &sParse); + }else{ + sqlite3_result_error_code(context, rc); + } + } + + renameParseCleanup(&sParse); + renameTokenFree(db, sCtx.pList); + sqlite3BtreeLeaveAll(db); +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = xAuth; +#endif + } + + return; +} + +static int renameQuotefixExprCb(Walker *pWalker, Expr *pExpr){ + if( pExpr->op==TK_STRING && (pExpr->flags & EP_DblQuoted) ){ + renameTokenFind(pWalker->pParse, pWalker->u.pRename, (const void*)pExpr); + } + return WRC_Continue; +} + +/* SQL function: sqlite_rename_quotefix(DB,SQL) +** +** Rewrite the DDL statement "SQL" so that any string literals that use +** double-quotes use single quotes instead. +** +** Two arguments must be passed: +** +** 0: Database name ("main", "temp" etc.). +** 1: SQL statement to edit. +** +** The returned value is the modified SQL statement. For example, given +** the database schema: +** +** CREATE TABLE t1(a, b, c); +** +** SELECT sqlite_rename_quotefix('main', +** 'CREATE VIEW v1 AS SELECT "a", "string" FROM t1' +** ); +** +** returns the string: +** +** CREATE VIEW v1 AS SELECT "a", 'string' FROM t1 +** +** If there is a error in the input SQL, then raise an error, except +** if PRAGMA writable_schema=ON, then just return the input string +** unmodified following an error. +*/ +static void renameQuotefixFunc( + sqlite3_context *context, + int NotUsed, + sqlite3_value **argv +){ + sqlite3 *db = sqlite3_context_db_handle(context); + char const *zDb = (const char*)sqlite3_value_text(argv[0]); + char const *zInput = (const char*)sqlite3_value_text(argv[1]); + +#ifndef SQLITE_OMIT_AUTHORIZATION + sqlite3_xauth xAuth = db->xAuth; + db->xAuth = 0; +#endif + + sqlite3BtreeEnterAll(db); + + UNUSED_PARAMETER(NotUsed); + if( zDb && zInput ){ + int rc; + Parse sParse; + rc = renameParseSql(&sParse, zDb, db, zInput, 0); + + if( rc==SQLITE_OK ){ + RenameCtx sCtx; + Walker sWalker; + + /* Walker to find tokens that need to be replaced. */ + memset(&sCtx, 0, sizeof(RenameCtx)); + memset(&sWalker, 0, sizeof(Walker)); + sWalker.pParse = &sParse; + sWalker.xExprCallback = renameQuotefixExprCb; + sWalker.xSelectCallback = renameColumnSelectCb; + sWalker.u.pRename = &sCtx; + + if( sParse.pNewTable ){ + if( IsView(sParse.pNewTable) ){ + Select *pSelect = sParse.pNewTable->u.view.pSelect; + pSelect->selFlags &= ~SF_View; + sParse.rc = SQLITE_OK; + sqlite3SelectPrep(&sParse, pSelect, 0); + rc = (db->mallocFailed ? SQLITE_NOMEM : sParse.rc); + if( rc==SQLITE_OK ){ + sqlite3WalkSelect(&sWalker, pSelect); + } + }else{ + int i; + sqlite3WalkExprList(&sWalker, sParse.pNewTable->pCheck); +#ifndef SQLITE_OMIT_GENERATED_COLUMNS + for(i=0; i<sParse.pNewTable->nCol; i++){ + sqlite3WalkExpr(&sWalker, + sqlite3ColumnExpr(sParse.pNewTable, + &sParse.pNewTable->aCol[i])); + } +#endif /* SQLITE_OMIT_GENERATED_COLUMNS */ + } + }else if( sParse.pNewIndex ){ + sqlite3WalkExprList(&sWalker, sParse.pNewIndex->aColExpr); + sqlite3WalkExpr(&sWalker, sParse.pNewIndex->pPartIdxWhere); + }else{ +#ifndef SQLITE_OMIT_TRIGGER + rc = renameResolveTrigger(&sParse); + if( rc==SQLITE_OK ){ + renameWalkTrigger(&sWalker, sParse.pNewTrigger); + } +#endif /* SQLITE_OMIT_TRIGGER */ + } + + if( rc==SQLITE_OK ){ + rc = renameEditSql(context, &sCtx, zInput, 0, 0); + } + renameTokenFree(db, sCtx.pList); + } + if( rc!=SQLITE_OK ){ + if( sqlite3WritableSchema(db) && rc==SQLITE_ERROR ){ + sqlite3_result_value(context, argv[1]); + }else{ + sqlite3_result_error_code(context, rc); + } + } + renameParseCleanup(&sParse); + } + +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = xAuth; +#endif + + sqlite3BtreeLeaveAll(db); +} + +/* Function: sqlite_rename_test(DB,SQL,TYPE,NAME,ISTEMP,WHEN,DQS) +** +** An SQL user function that checks that there are no parse or symbol +** resolution problems in a CREATE TRIGGER|TABLE|VIEW|INDEX statement. +** After an ALTER TABLE .. RENAME operation is performed and the schema +** reloaded, this function is called on each SQL statement in the schema +** to ensure that it is still usable. +** +** 0: Database name ("main", "temp" etc.). +** 1: SQL statement. +** 2: Object type ("view", "table", "trigger" or "index"). +** 3: Object name. +** 4: True if object is from temp schema. +** 5: "when" part of error message. +** 6: True to disable the DQS quirk when parsing SQL. +** +** The return value is computed as follows: +** +** A. If an error is seen and not in PRAGMA writable_schema=ON mode, +** then raise the error. +** B. Else if a trigger is created and the the table that the trigger is +** attached to is in database zDb, then return 1. +** C. Otherwise return NULL. +*/ +static void renameTableTest( + sqlite3_context *context, + int NotUsed, + sqlite3_value **argv +){ + sqlite3 *db = sqlite3_context_db_handle(context); + char const *zDb = (const char*)sqlite3_value_text(argv[0]); + char const *zInput = (const char*)sqlite3_value_text(argv[1]); + int bTemp = sqlite3_value_int(argv[4]); + int isLegacy = (db->flags & SQLITE_LegacyAlter); + char const *zWhen = (const char*)sqlite3_value_text(argv[5]); + int bNoDQS = sqlite3_value_int(argv[6]); + +#ifndef SQLITE_OMIT_AUTHORIZATION + sqlite3_xauth xAuth = db->xAuth; + db->xAuth = 0; +#endif + + UNUSED_PARAMETER(NotUsed); + + if( zDb && zInput ){ + int rc; + Parse sParse; + int flags = db->flags; + if( bNoDQS ) db->flags &= ~(SQLITE_DqsDML|SQLITE_DqsDDL); + rc = renameParseSql(&sParse, zDb, db, zInput, bTemp); + db->flags |= (flags & (SQLITE_DqsDML|SQLITE_DqsDDL)); + if( rc==SQLITE_OK ){ + if( isLegacy==0 && sParse.pNewTable && IsView(sParse.pNewTable) ){ + NameContext sNC; + memset(&sNC, 0, sizeof(sNC)); + sNC.pParse = &sParse; + sqlite3SelectPrep(&sParse, sParse.pNewTable->u.view.pSelect, &sNC); + if( sParse.nErr ) rc = sParse.rc; + } + + else if( sParse.pNewTrigger ){ + if( isLegacy==0 ){ + rc = renameResolveTrigger(&sParse); + } + if( rc==SQLITE_OK ){ + int i1 = sqlite3SchemaToIndex(db, sParse.pNewTrigger->pTabSchema); + int i2 = sqlite3FindDbName(db, zDb); + if( i1==i2 ){ + /* Handle output case B */ + sqlite3_result_int(context, 1); + } + } + } + } + + if( rc!=SQLITE_OK && zWhen && !sqlite3WritableSchema(db) ){ + /* Output case A */ + renameColumnParseError(context, zWhen, argv[2], argv[3],&sParse); + } + renameParseCleanup(&sParse); + } + +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = xAuth; +#endif +} + +/* +** The implementation of internal UDF sqlite_drop_column(). +** +** Arguments: +** +** argv[0]: An integer - the index of the schema containing the table +** argv[1]: CREATE TABLE statement to modify. +** argv[2]: An integer - the index of the column to remove. +** +** The value returned is a string containing the CREATE TABLE statement +** with column argv[2] removed. +*/ +static void dropColumnFunc( + sqlite3_context *context, + int NotUsed, + sqlite3_value **argv +){ + sqlite3 *db = sqlite3_context_db_handle(context); + int iSchema = sqlite3_value_int(argv[0]); + const char *zSql = (const char*)sqlite3_value_text(argv[1]); + int iCol = sqlite3_value_int(argv[2]); + const char *zDb = db->aDb[iSchema].zDbSName; + int rc; + Parse sParse; + RenameToken *pCol; + Table *pTab; + const char *zEnd; + char *zNew = 0; + +#ifndef SQLITE_OMIT_AUTHORIZATION + sqlite3_xauth xAuth = db->xAuth; + db->xAuth = 0; +#endif + + UNUSED_PARAMETER(NotUsed); + rc = renameParseSql(&sParse, zDb, db, zSql, iSchema==1); + if( rc!=SQLITE_OK ) goto drop_column_done; + pTab = sParse.pNewTable; + if( pTab==0 || pTab->nCol==1 || iCol>=pTab->nCol ){ + /* This can happen if the sqlite_schema table is corrupt */ + rc = SQLITE_CORRUPT_BKPT; + goto drop_column_done; + } + + pCol = renameTokenFind(&sParse, 0, (void*)pTab->aCol[iCol].zCnName); + if( iCol<pTab->nCol-1 ){ + RenameToken *pEnd; + pEnd = renameTokenFind(&sParse, 0, (void*)pTab->aCol[iCol+1].zCnName); + zEnd = (const char*)pEnd->t.z; + }else{ + assert( IsOrdinaryTable(pTab) ); + zEnd = (const char*)&zSql[pTab->u.tab.addColOffset]; + while( ALWAYS(pCol->t.z[0]!=0) && pCol->t.z[0]!=',' ) pCol->t.z--; + } + + zNew = sqlite3MPrintf(db, "%.*s%s", pCol->t.z-zSql, zSql, zEnd); + sqlite3_result_text(context, zNew, -1, SQLITE_TRANSIENT); + sqlite3_free(zNew); + +drop_column_done: + renameParseCleanup(&sParse); +#ifndef SQLITE_OMIT_AUTHORIZATION + db->xAuth = xAuth; +#endif + if( rc!=SQLITE_OK ){ + sqlite3_result_error_code(context, rc); + } +} + +/* +** This function is called by the parser upon parsing an +** +** ALTER TABLE pSrc DROP COLUMN pName +** +** statement. Argument pSrc contains the possibly qualified name of the +** table being edited, and token pName the name of the column to drop. +*/ +void sqlite3AlterDropColumn(Parse *pParse, SrcList *pSrc, const Token *pName){ + sqlite3 *db = pParse->db; /* Database handle */ + Table *pTab; /* Table to modify */ + int iDb; /* Index of db containing pTab in aDb[] */ + const char *zDb; /* Database containing pTab ("main" etc.) */ + char *zCol = 0; /* Name of column to drop */ + int iCol; /* Index of column zCol in pTab->aCol[] */ + + /* Look up the table being altered. */ + assert( pParse->pNewTable==0 ); + assert( sqlite3BtreeHoldsAllMutexes(db) ); + if( NEVER(db->mallocFailed) ) goto exit_drop_column; + pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]); + if( !pTab ) goto exit_drop_column; + + /* Make sure this is not an attempt to ALTER a view, virtual table or + ** system table. */ + if( SQLITE_OK!=isAlterableTable(pParse, pTab) ) goto exit_drop_column; + if( SQLITE_OK!=isRealTable(pParse, pTab, 1) ) goto exit_drop_column; + + /* Find the index of the column being dropped. */ + zCol = sqlite3NameFromToken(db, pName); + if( zCol==0 ){ + assert( db->mallocFailed ); + goto exit_drop_column; + } + iCol = sqlite3ColumnIndex(pTab, zCol); + if( iCol<0 ){ + sqlite3ErrorMsg(pParse, "no such column: \"%T\"", pName); + goto exit_drop_column; + } + + /* Do not allow the user to drop a PRIMARY KEY column or a column + ** constrained by a UNIQUE constraint. */ + if( pTab->aCol[iCol].colFlags & (COLFLAG_PRIMKEY|COLFLAG_UNIQUE) ){ + sqlite3ErrorMsg(pParse, "cannot drop %s column: \"%s\"", + (pTab->aCol[iCol].colFlags&COLFLAG_PRIMKEY) ? "PRIMARY KEY" : "UNIQUE", + zCol + ); + goto exit_drop_column; + } + + /* Do not allow the number of columns to go to zero */ + if( pTab->nCol<=1 ){ + sqlite3ErrorMsg(pParse, "cannot drop column \"%s\": no other columns exist",zCol); + goto exit_drop_column; + } + + /* Edit the sqlite_schema table */ + iDb = sqlite3SchemaToIndex(db, pTab->pSchema); + assert( iDb>=0 ); + zDb = db->aDb[iDb].zDbSName; +#ifndef SQLITE_OMIT_AUTHORIZATION + /* Invoke the authorization callback. */ + if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, zCol) ){ + goto exit_drop_column; + } +#endif + renameTestSchema(pParse, zDb, iDb==1, "", 0); + renameFixQuotes(pParse, zDb, iDb==1); + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." LEGACY_SCHEMA_TABLE " SET " + "sql = sqlite_drop_column(%d, sql, %d) " + "WHERE (type=='table' AND tbl_name=%Q COLLATE nocase)" + , zDb, iDb, iCol, pTab->zName + ); + + /* Drop and reload the database schema. */ + renameReloadSchema(pParse, iDb, INITFLAG_AlterDrop); + renameTestSchema(pParse, zDb, iDb==1, "after drop column", 1); + + /* Edit rows of table on disk */ + if( pParse->nErr==0 && (pTab->aCol[iCol].colFlags & COLFLAG_VIRTUAL)==0 ){ + int i; + int addr; + int reg; + int regRec; + Index *pPk = 0; + int nField = 0; /* Number of non-virtual columns after drop */ + int iCur; + Vdbe *v = sqlite3GetVdbe(pParse); + iCur = pParse->nTab++; + sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite); + addr = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v); + reg = ++pParse->nMem; + if( HasRowid(pTab) ){ + sqlite3VdbeAddOp2(v, OP_Rowid, iCur, reg); + pParse->nMem += pTab->nCol; + }else{ + pPk = sqlite3PrimaryKeyIndex(pTab); + pParse->nMem += pPk->nColumn; + for(i=0; i<pPk->nKeyCol; i++){ + sqlite3VdbeAddOp3(v, OP_Column, iCur, i, reg+i+1); + } + nField = pPk->nKeyCol; + } + regRec = ++pParse->nMem; + for(i=0; i<pTab->nCol; i++){ + if( i!=iCol && (pTab->aCol[i].colFlags & COLFLAG_VIRTUAL)==0 ){ + int regOut; + if( pPk ){ + int iPos = sqlite3TableColumnToIndex(pPk, i); + int iColPos = sqlite3TableColumnToIndex(pPk, iCol); + if( iPos<pPk->nKeyCol ) continue; + regOut = reg+1+iPos-(iPos>iColPos); + }else{ + regOut = reg+1+nField; + } + if( i==pTab->iPKey ){ + sqlite3VdbeAddOp2(v, OP_Null, 0, regOut); + }else{ + sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOut); + } + nField++; + } + } + if( nField==0 ){ + /* dbsqlfuzz 5f09e7bcc78b4954d06bf9f2400d7715f48d1fef */ + pParse->nMem++; + sqlite3VdbeAddOp2(v, OP_Null, 0, reg+1); + nField = 1; + } + sqlite3VdbeAddOp3(v, OP_MakeRecord, reg+1, nField, regRec); + if( pPk ){ + sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iCur, regRec, reg+1, pPk->nKeyCol); + }else{ + sqlite3VdbeAddOp3(v, OP_Insert, iCur, regRec, reg); + } + sqlite3VdbeChangeP5(v, OPFLAG_SAVEPOSITION); + + sqlite3VdbeAddOp2(v, OP_Next, iCur, addr+1); VdbeCoverage(v); + sqlite3VdbeJumpHere(v, addr); + } + +exit_drop_column: + sqlite3DbFree(db, zCol); + sqlite3SrcListDelete(db, pSrc); +} + +/* +** Register built-in functions used to help implement ALTER TABLE +*/ +void sqlite3AlterFunctions(void){ + static FuncDef aAlterTableFuncs[] = { + INTERNAL_FUNCTION(sqlite_rename_column, 9, renameColumnFunc), + INTERNAL_FUNCTION(sqlite_rename_table, 7, renameTableFunc), + INTERNAL_FUNCTION(sqlite_rename_test, 7, renameTableTest), + INTERNAL_FUNCTION(sqlite_drop_column, 3, dropColumnFunc), + INTERNAL_FUNCTION(sqlite_rename_quotefix,2, renameQuotefixFunc), + }; + sqlite3InsertBuiltinFuncs(aAlterTableFuncs, ArraySize(aAlterTableFuncs)); +} +#endif /* SQLITE_ALTER_TABLE */ |