MySQL? ????? ???? ??? ?????? ?? ?????, ??? ??? ??? ????? ?? ?? ???? ??? ?? ?? ?????. MySQL?? ???? ???? ??? ????, ??? ??? ??, ??? ??? ?? ??? ??? ? ?? ? ?? ??? ?????. ? ????? MySQL? ??? ? ??? ??? ?????.

1. ???

1. ??? ??

???? ???? ???? ????? ??? ??, ?? ?? ??? ? ?? ??? ??? ???? ????? MySQL? ?? ?? ???????. ???? BEFORE ???, AFTER ???, INSTEAD OF ???? ? ?? ??? ????. BEFORE ???? ??? ???? ?? ????, AFTER ???? ??? ??? ?? ????, INSTEAD OF ???? ??? ???? ?? ?? ??? ?????. ???? ?? ??? ?? ? ?? ??? ????, ?? ??, ?? ?? ? ?? ??? ???? ??? ? ????.

2. ??? ??

???? ????? CREATE TRIGGER ?? ???? ???. ??? ??? ????.

CREATE TRIGGER Trigger_name
BEFORE/AFTER/INSTEAD OF insert/update/delete
ON table_name
FOR EACH ROW
trigger_body

??? Trigger_name? ??? ???? insert/update/delete? ??? ?????. , table_name? ???? ?? ???? ????, Trigger_body? ???? ?? ?????. Trigger_body??? NEW? ???? ?? ??? ?? ???? OLD? ???? ?? ?? ??? ? ????.

3. ?

??? ?? ???? ? ???? ??? ? ???? ??? ??? ?? ???? ???? ????.

CREATE TABLE ?? (
id INT PRIMARY KEY AUTO_INCREMENT,
name VARCHAR( 100),
age INT
);

CREATE TABLE log (
id INT PRIMARY KEY AUTO_INCREMENT,
action VARCHAR(100),
timestamp TIMESTAMP
);

DELIMITER //
CREATE TRIGGER insert_log AFTER INSERT
???? ROW
BEGIN
INSERT INTO log (action, timestamp) VALUES ('insert', NOW());
END //

? ???? ???? ???? ???? ??? ???? ??? ?????. ??? ? ??? ?? ?? ? ?????? ??? ?? ??? ?????.

2. ???

1. ??? ??

???? MySQL?? ??? ????, ??? ??? ?? ????? ???? ? ????. ???? ?? ??? SQL ?, ?? ????? ????? ??? ?? ??? ??? ??? ? ????. ???? ???? ??? ??, ??? ??? ??, ??? ?? ?? ?? ?????? ??? ? ????.

2. ??? ??

???? ????? CREATE EVENT ?? ???? ???. ??? ??? ????.

CREATE EVENT event_name
ON SCHEDULE Schedule
[DO sql_statements]
[COMPLETION NOT PRESERVE]
[ENABLE/DISABLE]

??? event_name? ??? ????, ???? ???? ????? ?? ??????. sql_statements? ???? ? ??? ??? SQL ? ?? ?? ???? ?????. COMPLETION ? ENABLE/DISABLE? ???? ?? ??? ????? ??? ???? ?? ??? ?? ?????? ? ???? ??? ?? ?????.

3. ?

??? ?? ?? ?????? ?? ??? ???? ????.

CREATE EVENT backup_event
ON SCHEDULE EVERY 1 DAY
STARTS '2022-01-01 00:00:00'
DO
BEGIN

-- 執(zhí)行備份操作

END;

backup_event ???? ??? ? ? ???? ??? ?? ???? ???? ???? ?????. ???? ????? BEGIN? END ??? SQL ??? ?????.

??:

???? ???? ?? MySQL?? ?? ?? ??? ?? ? ?? ??? ??? ? ????. ???? ???? ??? ? ?? ??? ???? ???? ? ??? ???? ?? ??? ????? ??? ? ????. ??? ???? ???? MySQL? ??? ??? ? ? ???? ?? ???? ??? ??? ???? ? ????.

? ?? ??? ?? ???? MySQL?? ???? ???? ???? ??? ?? ?? ?? ???? ?? ???? ???? ???? ?? ???? ?????? ??? ?? ? ??? ????.

? ??? MySQL?? ???? ???? ???? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!