mysql - How to keep two table's data consistent when deleting records from one of them? -
say, have 2 tables: students , course_scores .
the attributes in students student_id, name, sex;
while attributes in course_scores student_id, course, score.
when delete records students, corresponding records in course_scores should deleted, right? create them consistency.
could show me codes this?
alter table course_scores add together foreign key (student_id) references students (student_id) on delete cascade
the on delete cascade part want; delete rows in course_scores if corresponding student_id deleted. tables must utilize innodb engine.
mysql database database-design foreign-keys
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