importsqlite3# 连接到数据库或创建一个新的数据库文件conn=sqlite3.connect('mydatabase.db')# 创建一个游标对象cursor=conn.cursor()# 执行删除表格的SQL语句cursor.execute("DROP TABLE IF EXISTS mytable")# 提交事务conn.commit()# 关闭游标和连接cursor.close()conn.close() 1. 2. 3. 4. 5. 6. ...
-DropTable: - (BOOL)dropTable:(NSString *)tableName { NSString * queryBase = [NSString stringWithFormat:@“drop table if if %%;”,tableName]; const char * query = [queryBase UTF8String]; sqlite3_stmt * stmt = nil; if(sqlite3_prepare_v2([SLDBAccess sharedSLDBAccess] .database,quer...
If I use the syntax "DROP TABLE tablename" everything is good, except of course I get a "no such table" error if the table does not exist. However, if I use the syntax "DROP TABLE IF EXISTS tablename", then I get the following error: 'near "EXISTS": syntax error'. Anyone have...
db, err = gorm.Open("sqlite3","hugocms_"+auth.UserName+".db") }iferr !=nil{ handleError(err) } db.LogMode(true)// to reset to an empty database drop the settings tableif!db.HasTable(&models.Settings{}) {for_, table :=rangehugocms_qor.Tables {iferr := db.DropTableIfExists(...
validate_access_permission(["w", "a"]) if table_name in SQLITE_SYSTEM_TABLES: # warning message return if self.has_table(table_name): query = "DROP TABLE IF EXISTS '{:s}'".format(table_name) self.execute_query(query, logging.getLogger().findCaller()) self.commit() ...
CREATE TABLE t1(id INTEGER); SQL # 3. Drop an unqualified (main.)t1 in presence of a.t1: cat <<SQL | sqlite3 c.sqlite ATTACH DATABASE 'a.sqlite' AS a; DROP TABLE IF EXISTS t1; -- Drops a.t1 !!?! SQL This caught me rather by surprise. I guess my expectation was that ...
DELETE QUERY OR DROP TABLE AND RE-GENERATE THE TABLE? 及关于删除sqlite里面所有数据,用drop并重建比delete all sqlite里面的数据更加有效率 itismore efficienttodroptableandre-createit;andyes, You can use "IF EXISTS"inthiscase DELETEFROMwill cause SQLitetovisit individualrowsunless thoserowshave trigger...
DROP TABLE IF EXISTS table2; DROP TABLE IF EXISTS table3; Remember to turn on foreign key constraint after it’s done: SET FOREIGN_KEY_CHECKS = 1; 2. Using mysqldump There’s another workaround with mysqldump which is faster and easier. ...
Add $ifExists and $cascade to dropTable() methods yiisoft/db#880 Open vjik added the status:under development label Sep 17, 2024 samdark approved these changes Sep 17, 2024 View reviewed changes Sign up for free to join this conversation on GitHub. Already have an account? Sign in ...
Submitted by: eXandr (i.reg) Votes: 4 It should be possible to determine not cause an error when deleting an object that does not exist Something like that: execute statement 'ALTER TABLE SOME_TABLE DROP [IF EXISTS] SOME_FIELD'; -- no ra...