DELIMITER
CREATE PROCEDURE AddColumnIfNotExists()
BEGIN
DECLARE CONTINUE HANDLER FOR 1060 -- Error code for duplicate column name
BEGIN
-- Column already exists; do nothing
END;
-- Check if the column exists
SELECT COUNT(*)
INTO @column_exists
FROM information_schema.columns
WHERE table_name = 'enter-name-here' AND column_name = 'enter-name-here';
-- If the column does not exist, add it
IF @column_exists = 0 THEN
ALTER TABLE `enter-database-name`.`enter-table-name`
ADD COLUMN `enter-column-name` VARCHAR(255) NULL DEFAULT NULL AFTER `enter-column-name`;
END IF;
END;