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22 Φεβ 2017 · Using Exists statement to delete data from table: IF EXISTS(SELECT 1 FROM Your_table WHERE user_id = user_id) BEGIN DELETE FROM Your_table WHERE user_id= user_id END Delete table from database : IF EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'TheSchema' AND TABLE_NAME = 'TheTable') BEGIN --Your delete statement END
DROP {DATABASE | SCHEMA} [IF EXISTS] db_name. DROP DATABASE drops all tables in the database and deletes the database. Be very careful with this statement! To use DROP DATABASE, you need the DROP privilege on the database. DROP SCHEMA is a synonym for DROP DATABASE.
Syntax. DROP DATABASE databasename; Note: Be careful before dropping a database. Deleting a database will result in loss of complete information stored in the database! DROP DATABASE Example. The following SQL statement drops the existing database "testDB": Example Get your own SQL Server. DROP DATABASE testDB;
10 Οκτ 2011 · sql = "DELETE FROM `#{database}`.`table1` WHERE `same_id` = #{some_id};" The problem is that in rare circumstances table1 might not exist. I need to construct this query so even if the table does not exist SQL does not throw an error. How can I implement this?
25 Ιαν 2024 · Use the IF EXISTS option to prevent errors in case the database does not exist. This command locks the database during the deletion process, which might be a performance consideration if run during peak hours. Solution 2: Dropping Databases Using MySQL Workbench.
If you drop a database that does not exist, MySQL will issue an error. To prevent an error from occurring if you delete a non-existing database, you can use the IF EXISTS option. In this case, MySQL will terminate the statement without issuing any error.
Single-Table Syntax. DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name [[AS] tbl_alias] [PARTITION (partition_name [, partition_name] ...)] [WHERE where_condition] [ORDER BY ...] [LIMIT row_count] The DELETE statement deletes rows from tbl_name and returns the number of deleted rows.
