diff options
Diffstat (limited to 'src/alter.c')
| -rw-r--r-- | src/alter.c | 273 |
1 files changed, 235 insertions, 38 deletions
diff --git a/src/alter.c b/src/alter.c index 0f50f195e..e34a592be 100644 --- a/src/alter.c +++ b/src/alter.c @@ -49,16 +49,21 @@ static int isAlterableTable(Parse *pParse, Table *pTab){ ** statement to ensure that the operation has not rendered any schema ** objects unusable. */ -static void renameTestSchema(Parse *pParse, const char *zDb, int bTemp){ +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 */ +){ pParse->colNamesSet = 1; sqlite3NestedParse(pParse, "SELECT 1 " "FROM \"%w\"." DFLT_SCHEMA_TABLE " " "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" " AND sql NOT LIKE 'create virtual%%'" - " AND sqlite_rename_test(%Q, sql, type, name, %d)=NULL ", + " AND sqlite_rename_test(%Q, sql, type, name, %d, %Q)=NULL ", zDb, - zDb, bTemp + zDb, bTemp, zWhen ); if( bTemp==0 ){ @@ -67,8 +72,8 @@ static void renameTestSchema(Parse *pParse, const char *zDb, int bTemp){ "FROM temp." DFLT_SCHEMA_TABLE " " "WHERE name NOT LIKE 'sqliteX_%%' ESCAPE 'X'" " AND sql NOT LIKE 'create virtual%%'" - " AND sqlite_rename_test(%Q, sql, type, name, 1)=NULL ", - zDb + " AND sqlite_rename_test(%Q, sql, type, name, 1, %Q)=NULL ", + zDb, zWhen ); } } @@ -77,12 +82,12 @@ static void renameTestSchema(Parse *pParse, const char *zDb, int bTemp){ ** 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){ +static void renameReloadSchema(Parse *pParse, int iDb, u16 p5){ Vdbe *v = pParse->pVdbe; if( v ){ sqlite3ChangeCookie(pParse, iDb); - sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, iDb, 0); - if( iDb!=1 ) sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, 1, 0); + sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, iDb, 0, p5); + if( iDb!=1 ) sqlite3VdbeAddParseSchemaOp(pParse->pVdbe, 1, 0, p5); } } @@ -231,7 +236,7 @@ void sqlite3AlterRenameTable( "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) " + " sqlite_rename_test(%Q, sql, type, name, 1, 'after rename') " "THEN %Q ELSE tbl_name END " "WHERE type IN ('view', 'trigger')" , zDb, zTabName, zName, zTabName, zDb, zName); @@ -250,8 +255,8 @@ void sqlite3AlterRenameTable( } #endif - renameReloadSchema(pParse, iDb); - renameTestSchema(pParse, zDb, iDb==1); + renameReloadSchema(pParse, iDb, INITFLAG_AlterRename); + renameTestSchema(pParse, zDb, iDb==1, "after rename"); exit_rename_table: sqlite3SrcListDelete(db, pSrc); @@ -413,7 +418,7 @@ void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){ } /* Reload the table definition */ - renameReloadSchema(pParse, iDb); + renameReloadSchema(pParse, iDb, INITFLAG_AlterRename); } /* @@ -513,7 +518,7 @@ exit_begin_add_column: ** 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){ +static int isRealTable(Parse *pParse, Table *pTab, int bDrop){ const char *zType = 0; #ifndef SQLITE_OMIT_VIEW if( pTab->pSelect ){ @@ -526,15 +531,16 @@ static int isRealTable(Parse *pParse, Table *pTab){ } #endif if( zType ){ - sqlite3ErrorMsg( - pParse, "cannot rename columns of %s \"%s\"", zType, pTab->zName + 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) (0) +# define isRealTable(x,y,z) (0) #endif /* @@ -563,7 +569,7 @@ void sqlite3AlterRenameColumn( /* Cannot alter a system table */ if( SQLITE_OK!=isAlterableTable(pParse, pTab) ) goto exit_rename_column; - if( SQLITE_OK!=isRealTable(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); @@ -617,8 +623,8 @@ void sqlite3AlterRenameColumn( ); /* Drop and reload the database schema. */ - renameReloadSchema(pParse, iSchema); - renameTestSchema(pParse, zDb, iSchema==1); + renameReloadSchema(pParse, iSchema, INITFLAG_AlterRename); + renameTestSchema(pParse, zDb, iSchema==1, "after rename"); exit_rename_column: sqlite3SrcListDelete(db, pSrc); @@ -870,23 +876,33 @@ static void renameTokenFree(sqlite3 *db, RenameToken *pToken){ /* ** Search the Parse object passed as the first argument for a RenameToken -** object associated with parse tree element pPtr. If found, remove it -** from the Parse object and add it to the list maintained by the -** RenameCtx object passed as the second argument. +** 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 void renameTokenFind(Parse *pParse, struct RenameCtx *pCtx, void *pPtr){ +static RenameToken *renameTokenFind( + Parse *pParse, + struct RenameCtx *pCtx, + void *pPtr +){ RenameToken **pp; assert( pPtr!=0 ); for(pp=&pParse->pRename; (*pp); pp=&(*pp)->pNext){ if( (*pp)->p==pPtr ){ RenameToken *pToken = *pp; - *pp = pToken->pNext; - pToken->pNext = pCtx->pList; - pCtx->pList = pToken; - pCtx->nList++; - break; + if( pCtx ){ + *pp = pToken->pNext; + pToken->pNext = pCtx->pList; + pCtx->pList = pToken; + pCtx->nList++; + } + return pToken; } } + return 0; } /* @@ -957,7 +973,7 @@ static RenameToken *renameColumnTokenNext(RenameCtx *pCtx){ */ static void renameColumnParseError( sqlite3_context *pCtx, - int bPost, + const char *zWhen, sqlite3_value *pType, sqlite3_value *pObject, Parse *pParse @@ -966,8 +982,8 @@ static void renameColumnParseError( const char *zN = (const char*)sqlite3_value_text(pObject); char *zErr; - zErr = sqlite3_mprintf("error in %s %s%s: %s", - zT, zN, (bPost ? " after rename" : ""), + zErr = sqlite3_mprintf("error in %s %s%s%s: %s", + zT, zN, (zWhen[0] ? " " : ""), zWhen, pParse->zErrMsg ); sqlite3_result_error(pCtx, zErr, -1); @@ -1473,7 +1489,7 @@ static void renameColumnFunc( renameColumnFunc_done: if( rc!=SQLITE_OK ){ if( sParse.zErrMsg ){ - renameColumnParseError(context, 0, argv[1], argv[2], &sParse); + renameColumnParseError(context, "", argv[1], argv[2], &sParse); }else{ sqlite3_result_error_code(context, rc); } @@ -1662,7 +1678,7 @@ static void renameTableFunc( } if( rc!=SQLITE_OK ){ if( sParse.zErrMsg ){ - renameColumnParseError(context, 0, argv[1], argv[2], &sParse); + renameColumnParseError(context, "", argv[1], argv[2], &sParse); }else{ sqlite3_result_error_code(context, rc); } @@ -1691,6 +1707,7 @@ static void renameTableFunc( ** 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. ** ** Unless it finds an error, this function normally returns NULL. However, it ** returns integer value 1 if: @@ -1708,6 +1725,7 @@ static void renameTableTest( 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]); #ifndef SQLITE_OMIT_AUTHORIZATION sqlite3_xauth xAuth = db->xAuth; @@ -1740,8 +1758,8 @@ static void renameTableTest( } } - if( rc!=SQLITE_OK ){ - renameColumnParseError(context, 1, argv[2], argv[3], &sParse); + if( rc!=SQLITE_OK && zWhen ){ + renameColumnParseError(context, zWhen, argv[2], argv[3],&sParse); } renameParseCleanup(&sParse); } @@ -1752,13 +1770,192 @@ static void renameTableTest( } /* +** 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. +** argv[3]: Byte offset of first byte after last column definition in argv[1] +** +** 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]); + int iAddColOffset = sqlite3_value_int(argv[3]); + 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 + + rc = renameParseSql(&sParse, zDb, db, zSql, iSchema==1); + if( rc!=SQLITE_OK ) goto drop_column_done; + pTab = sParse.pNewTable; + + pCol = renameTokenFind(&sParse, 0, (void*)pTab->aCol[iCol].zName); + if( iCol<pTab->nCol-1 ){ + RenameToken *pEnd; + pEnd = renameTokenFind(&sParse, 0, (void*)pTab->aCol[iCol+1].zName); + zEnd = (const char*)pEnd->t.z; + }else{ + zEnd = (const char*)&zSql[iAddColOffset]; + while( pCol->t.z[0]!=',' && pCol->t.z[1]!='(' ) 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 +} + +/* +** 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, 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( 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: \"%s\"", zCol); + 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; + } + + /* Edit the sqlite_schema table */ + iDb = sqlite3SchemaToIndex(db, pTab->pSchema); + assert( iDb>=0 ); + zDb = db->aDb[iDb].zDbSName; + renameTestSchema(pParse, zDb, iDb==1, ""); + sqlite3NestedParse(pParse, + "UPDATE \"%w\"." DFLT_SCHEMA_TABLE " SET " + "sql = sqlite_drop_column(%d, sql, %d, %d) " + "WHERE (type=='table' AND tbl_name=%Q COLLATE nocase)" + , zDb, iDb, iCol, pTab->addColOffset, pTab->zName + ); + + /* Drop and reload the database schema. */ + renameReloadSchema(pParse, iDb, INITFLAG_AlterDrop); + renameTestSchema(pParse, zDb, iDb==1, "after drop column"); + + /* 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); + reg = ++pParse->nMem; + pParse->nMem += pTab->nCol; + if( HasRowid(pTab) ){ + sqlite3VdbeAddOp2(v, OP_Rowid, iCur, reg); + }else{ + pPk = sqlite3PrimaryKeyIndex(pTab); + } + 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); + regOut = reg+1+iPos-(iPos>iColPos); + }else{ + regOut = reg+1+nField; + } + sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOut); + nField++; + } + } + regRec = reg + pTab->nCol; + 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); + } + + sqlite3VdbeAddOp2(v, OP_Next, iCur, addr+1); + 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, 5, renameTableTest), + INTERNAL_FUNCTION(sqlite_rename_column, 9, renameColumnFunc), + INTERNAL_FUNCTION(sqlite_rename_table, 7, renameTableFunc), + INTERNAL_FUNCTION(sqlite_rename_test, 6, renameTableTest), + INTERNAL_FUNCTION(sqlite_drop_column, 4, dropColumnFunc), }; sqlite3InsertBuiltinFuncs(aAlterTableFuncs, ArraySize(aAlterTableFuncs)); } |