mysql触发更新操作问题

Question

hi all am a beginner in php

Am working on trigger i need to insert the changed values in trigger table when the tables get updated,while inserting in trigger i need the column name of the changed fields so i have tried the following code but it not working only it accepts one condition on trigger its not possible to set multiple triggers for a single table help me to solve this issues

IF NEW.account_holder <> OLD.account_holder THEN  

    INSERT INTO bank_trigger (filed_name) VALUES('account');

END IF

IF NEW.branch_name <> OLD.branch_name THEN  

    INSERT INTO bank_trigger (filed_name) VALUES('branch_name');

END IF;

Answer 1

Before I used this

DROP TRIGGER IF EXISTS some_trigger;

DELIMITER $$

CREATE TRIGGER `some_trigger` AFTER UPDATE ON `table_1` FOR EACH ROW 
    BEGIN

        IF !(OLD.a <=> NEW.a AND OLD.b <=> NEW.b) THEN
            INSERT INTO `table_2` (
                `a`,
                 `b`
            ) VALUES (
                NEW.`a`,
                NEW.`b`
            );
        END IF;
    END;$$

DELIMITER ;