Table1 "user_address"
Field "u_id"
Field "street_name"
Field "locality_name"
Table2 "street_master"
Field "s_id"
Field "s_name"
I am supposed to write a trigger which BEFORE INSERT ON user_address(table1) checks if NEW.street_name already exists in s_name in table2, and
if it does not exist then NEW.street_name is inserted in table2.
I don't know how to do it . It has to be done by trigger only.
Best Answer
Given your table structure:
This will do the job:
To test:
I suggest you read the MySQL documentation on triggers and learn for yourself.