how to say create procedure if not exist in MySQL

问题

I am trying to write a script to create a procedure in MySQL database, but I want to check if it exsit first.

I know how to do it for a table, but when I use the same syntax for stored procedure, it doesn't compile.

Does anybody know? Thanks

回答1:

Just drop the procedure if it does exist and then re-add it:

DROP PROCEDURE IF EXISTS my_procedure;
CREATE PROCEDURE my_procedure()

回答2:

SELECT EXISTS(SELECT 1 FROM mysql.proc p WHERE db = 'db_name' AND name = 'stored_proc_name');

So you could do:

IF NOT EXISTS(SELECT 1 FROM mysql.proc p WHERE db = 'db_name' AND name = 'stored_proc_name') THEN
....
END IF;

回答3:

It doesn't exist. We had to write a stored procedure that mimics the same functionality. Basically we create stored procedures by calling a stored procedure that does the "if exists" check.

来源：https://stackoverflow.com/questions/9948713/how-to-say-create-procedure-if-not-exist-in-mysql