NOTE: Before marking it as Duplicate, i want to tell you guys that i've gone through all these related problems in stackoverflow and other websites, but i didn't get any suitable solution, so that's why i am here for the help.
I have two tables: employees and fines
In fines table fine_id
is the PK and employee_id
is the FK references to employees table PK employee_id
.
Now, i am creating fine_id
(column in table employees ) as a FK reference to fine_id
in fines table.
i am adding constraints via XAMPP PHPMYADMIN it auto generates my query which is:
ALTER TABLE employees ADD CONSTRAINT fine_fk FOREIGN KEY (fine_id) REFERENCES fines(fine_id) ON DELETE CASCADE ON UPDATE CASCADE;
But, I am getting this error while running this SQL Query
ems_db
. #sql-dd4_35
, CONSTRAINT fine_fk
FOREIGN KEY ( fine_id
) REFERENCES fines
( fine_id
) ON DELETE CASCADE ON UPDATE CASCADE) Here are attached images:
employees table
fines table
error
Thanks.
somehow i managed to solve my issue myself,
the problem was that in my employees table i have the column fine_id
which i want to make a FK , that column value was empty in my existing record in employees table, although i have values in my fines table, but the column fine_id
in employees table was not filled, with the corresponding fine_id
of fines table, so before creating FK i have filled my column with the correct ID's of fines table, and my problem was gone away.
I will suggest to use query to set foreign key. Not graphically. That worked for me!
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.