List of constraints in the database

Question

How to get a list of all constraints from a MySQL database?

Answer 1

Use information_schema.table_constraints table to get the name of the constraints defined on each table:

select *
from information_schema.table_constraints
where constraint_schema = 'YOUR_DB'

Use information_schema.key_column_usage table to obtain the fields in these constraints:

select *
from information_schema.key_column_usage
where constraint_schema = 'YOUR_DB'

If you want to discuss foreign key constraints, use information_schema.referential_constraints:

select *
from information_schema.referential_constraints
where constraint_schema = 'YOUR_DB'