mysql判斷表中欄位或者索引是否存在，如果不存在則建立
阿新 • • 發佈：2019-01-23
判斷欄位是否存在：
DROP PROCEDURE IF EXISTS schema_change; DELIMITER // CREATE PROCEDURE schema_change() BEGIN DECLARE CurrentDatabase VARCHAR(100); SELECT DATABASE() INTO CurrentDatabase; IF NOT EXISTS (SELECT * FROM information_schema.statistics WHERE table_schema=CurrentDatabase AND table_name = 'rtc_phototype' AND index_name = 'index_name') THEN ALTER TABLE `rtc_Phototype` ADD INDEX index_name ( `imgtype` ); END IF; END// DELIMITER ; CALL schema_change();
判斷索引是否存在：
DROP PROCEDURE IF EXISTS schema_change; DELIMITER // CREATE PROCEDURE schema_change() BEGIN DECLARE CurrentDatabase VARCHAR(100); SELECT DATABASE() INTO CurrentDatabase; IF NOT EXISTS (SELECT * FROM information_schema.statistics WHERE table_schema=CurrentDatabase AND table_name = 'rtc_phototype' AND index_name = 'index_name') THEN ALTER TABLE `rtc_Phototype` ADD INDEX index_name ( `imgtype` ); END IF; END// DELIMITER ; CALL schema_change();