I\'m having a bit of a strange problem. I\'m trying to add a foreign key to one table that references another, but it is failing for some reason. With my limited knowledge o
Quite likely your sourcecodes_tags
table contains sourcecode_id
values that no longer exists in your sourcecodes
table. You have to get rid of those first.
Here's a query that can find those IDs:
SELECT DISTINCT sourcecode_id FROM
sourcecodes_tags tags LEFT JOIN sourcecodes sc ON tags.sourcecode_id=sc.id
WHERE sc.id IS NULL;