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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.
DROP FUNCTION [IF EXISTS] function_name; Code language: SQL (Structured Query Language) (sql) In this syntax, you specify the name of the stored function that you want to drop after the DROP FUNCTION keywords. The IF EXISTS option allows you to conditionally drop a stored function if it exists.
The MySQL DROP DATABASE Statement. The DROP DATABASE statement is used to drop an existing SQL 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.
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.
7 Σεπ 2024 · Let’s explore the syntax of dropping a table only if it exists in a database: DROP TABLE IF EXISTS table_name; Here: DROP TABLE deletes a table and all of its content from a database; IF EXISTS is a conditional modifier that checks if the specified table exists in the database before attempting to drop it.
DROP FUNCTION [IF EXISTS] function_name. This statement drops the loadable function named function_name. (DROP FUNCTION is also used to drop stored functions; see Section 15.1.29, “DROP PROCEDURE and DROP FUNCTION Statements”.) DROP FUNCTION is the complement of CREATE FUNCTION.
