Mysql triggers passing data from one table to another matching tables - mysql

Question

I've table1 with columns (id, firstname, lastname) and table2 with columns (id, firstname, lastname, ans3, mandate, matchid). So far i've made this trigger that inserts firstname and lastname from table1 to table2. Now the thing that i want is to join the matchid from table2 with the id from table1. For example when matchid = 1 display records from table1 with id = 1 and in the same row the table2 records. Here's what i do so far with the trigger.
DELIMITER //
CREATE TRIGGER after_user_insert AFTER INSERT ON table1
FOR EACH ROW
BEGIN
INSERT INTO table2 (firstname, lastname, matchid)
VALUES (NEW.firstname, NEW.lastname, NEW.id);
END; //
DELIMITER ;
Here's a photo of what i get in phpmyadmin. You can see that i didn't figure how to join table2.matchid to table1.id
---edit---

Answer 1

From your comments it sounds like perhaps you intended to update a user record which already exists in table2. If so, you can use ON DUPLICATE KEY when you update:
DELIMITER //
CREATE TRIGGER after_user_insert AFTER INSERT ON table1
FOR EACH ROW
BEGIN
INSERT INTO table2 (firstname, lastname, matchid)
VALUES (NEW.firstname, NEW.lastname, NEW.id)
ON DUPLICATE KEY UPDATE matchid = NEW.id;
END; //
DELIMITER ;
This solution would require that there is a unique index on both the first and last name in table2. If you don't have such a unique index, then you can add one:
ALTER TABLE table2 ADD UNIQUE unq_idx (firstname, lastname);