MySQL 8.0

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CREATE tABLE Cvr_hooks_501_1000(post_author_id vaRCHAR(39))
INSERT INTO Cvr_hooks_501_1000 VALUES ("1")
CREATE TABLE account(hook_id int, user_id int(11) ,post_id int, post_author_id int)
CREATE TABLE Cvr_1_link_501_1000 (a_hook_id int, a_user_id int(11) ,a_post_id int, a_post_author_id int)
CREATE TRIGGER upd_check AFTER  INSERT ON account
       FOR EACH ROW
       BEGIN
		IF ( EXISTS(SELECT 1 FROM Cvr_hooks_501_1000 WHERE post_author_id =  new.user_id)) then
			
			INSERT INTO Cvr_1_link_501_1000 (a_hook_id, a_user_id, a_post_id, a_post_author_id)

			VALUES (new.hook_id, 
					new.user_id, 
					new.post_id, 
					new.post_author_id);

			END IF;

       END
INSERT INTO account VALUES(1,1,1,1)
SELECT * FROM Cvr_1_link_501_1000


a_hook_id
a_user_id
a_post_id
a_post_author_id


1
1
1
1