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MySQL Many relational problems
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MySQL Many relational problems
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I have 3 tables in mysql artists tracks and artist_tracks and i did what was written in this aricle.
this is the tables artist:artist_id, artist_name tracks:track_id, track_name artist_tracks: artist_id, track_id
how can i prevent duplicate rows in artist_tracks table ??
Create a composite primary key around both the artist_id and track_id columns. This is standard practice for bridge tables.
ALTER TABLE artist_tracks DROP PRIMARY KEY;
ALTER TABLE artist_tracks ADD PRIMARY KEY (artist_id, track_id);
If you followed that article correctly, you should already have such a key and so duplicates will be impossible.
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