On Wed May 10, 2017 at 08:34:42AM +0200, Clemens Ladisch wrote:
> Mark Wagner wrote:
> > Is there a way to get sqlite to tell which foreign key constraint is
> > causing a failure?
>
> No; to make the implementation of deferred constraints easier, it keeps
> track only of the number of remaining foreign key failures, not of their
> origin.
Maybe; If you are developing and can afford to reload/reset invalid
data you can turn off foreign key support and do the DELETE, and then
run the foreign_key_check pragma:
CREATE TABLE a(
id INTEGER PRIMARY KEY
);
CREATE TABLE b(
id INTEGER,
FOREIGN KEY(id) REFERENCES a(id)
);
INSERT INTO a VALUES(1);
INSERT INTO b VALUES(1);
DELETE FROM a;
-- Error: FOREIGN KEY constraint failed
PRAGMA foreign_keys=0;
DELETE FROM a;
-- No Error, but now your data is invalid
PRAGMA foreign_key_check;
-- table rowid parent fkid
-- ---------- ---------- ---------- ----------
-- b 1 a 0
You could perhaps even run the DELETE inside a transaction and rollback
once you have obtained the information you need, to keep your data
integrity.
Regards,
Mark
--
Mark Lawrence
_______________________________________________
sqlite-users mailing list
[email protected]
http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
