在第三个表上插入后，触发为在另一个表中的每一行的表中插入元组

Question

I have three table council_member, mess and rates.

council_member(student_id, field2,...)
mess(mess_id,field2,...)
rates(student_id,mess_id,rating)

student_id and mess_id are foreign keys.

Rates stores the rating for each mess by each council member. I want to create a trigger that on insertion of a new council member, inserts tupples to the table rates for the inserted student_id and each mess_id in mess with a rating of 10.

How do I run the insert statement in trigger for each mess_id?

Answer 1

This works great

CREATE TRIGGER insert_council_member 
AFTER INSERT ON council_member
FOR EACH ROW 
  INSERT INTO rates SELECT NEW.student_id, mess_id, 10 FROM mess;

http://sqlfiddle.com/#!2/ac4a0/1