Re: How do I create my table to avoid java.sql.SQLIntegrityConstraintViolationException: Duplicate entry '' for key 'PRIMARY'
Posted by: Filipe Silva
Date: January 02, 2019 04:28AM

Hi Karen,

Cascade deletes are defined with foreign keys, not primary keys.

If that's what you really want, your `tutor_subject` table could be created like this:

CREATE TABLE tutor_subject (
tutor_id INT NOT NULL,
subjectName Varchar(50) NOT NULL,
FOREIGN KEY (tutor_id) REFERENCES tutors (tutor_id) ON DELETE CASCADE)
Engine=InnoDB Default charset=utf8mb4

This way, when you delete a tutor record from the "tutors" table, the tutor/subject records from the "tutor_subject" table are also deleted for the same "tutor_id".


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