Leaves what's there alone and just starts enforcing from when you turn it on. It'll only go actively looking for issues if you do a pragma foreign_key_check;
sqlite> pragma foreign_keys = off; sqlite> create table parent (id integer primary key); sqlite> create table child (id integer primary key, parentID int references parent); sqlite> insert into parent values (1), (2); sqlite> insert into child (parentID) values (1), (2), (3), (4); sqlite> pragma foreign_key_check; table|rowid|parent|fkid child|3|parent|0 child|4|parent|0 sqlite> pragma foreign_keys = on; sqlite> insert into parent values (3); sqlite> update child set parentID = parentID + 1; Error: FOREIGN KEY constraint failed sqlite> pragma foreign_key_check; table|rowid|parent|fkid child|4|parent|0 -----Original Message----- From: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] On Behalf Of x Sent: Tuesday, November 28, 2017 10:27 AM To: sqlite-users@mailinglists.sqlite.org Subject: [sqlite] Foreign key help If I have foreign keys in place but always have foreign_keys = OFF then one day start SQLite with foreign_keys = ON what happens? Does SQLite suddenly check all foreign keys and report / delete violations or does it leave everything as is and just enforce foreign keys from that point on? _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
