In reply to a question about how to conditionally drop an index on a table in MySQL. It appears the syntax doesn’t exist. However, maybe it does and I missed it. If I did miss it, I’m sure somebody will let me know. However, I simply have a dropIndexIfExists stored procedure for this type of database maintenance.
Below is my dropIndexIfExists stored procedure:
-- Conditionally drop the procedure. DROP PROCEDURE IF EXISTS dropIndexIfExists; -- Change the default semicolon delimiter to write a PSM -- (Persistent Stored Module) or stored procedure. DELIMITER $$ -- Create the procedure. CREATE PROCEDURE dropIndexIfExists ( pv_table_name VARCHAR(64) , pv_index_name VARCHAR(64)) BEGIN /* Declare a local variable for the SQL statement. */ DECLARE stmt VARCHAR(1024); /* Set a session variable with two parameter markers. */ SET @SQL := CONCAT('ALTER TABLE ',pv_table_name,'DROP INDEX ',pv_index_name); /* Check if the constraint exists. …[Read more]