How can I temporarily disable a foreign key constraint in MySQL?

Is it possible to temporarily disable constraints in MySQL?

I have two Django models, each with a foreign key to the other one. Deleting instances of a model returns an error because of the foreign key constraint:

cursor.execute("DELETE FROM myapp_item WHERE n = %s", n)
transaction.commit_unless_managed()  #a foreign key constraint fails here

cursor.execute("DELETE FROM myapp_style WHERE n = %s", n)
transaction.commit_unless_managed()

​x
 
cursor.execute("DELETE FROM myapp_item WHERE n = %s", n)transaction.commit_unless_managed()  #a foreign key constraint fails here​cursor.execute("DELETE FROM myapp_style WHERE n = %s", n)transaction.commit_unless_managed()​

Is it possible to temporarily disable constraints and delete anyway?

Answer

Try DISABLE KEYS or

SET FOREIGN_KEY_CHECKS=0;

 
SET FOREIGN_KEY_CHECKS=0;​

Make sure to

SET FOREIGN_KEY_CHECKS=1;

 
SET FOREIGN_KEY_CHECKS=1;​

after.

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Answer