fix_mixxx_db.md

Fixing Mixxx's Database

As mentionned in this issue several foreign key constraints defined in Mixxx's database are incorrect, and SQL Alchemy (Python's library) does not like it.

I fixed these quite easily using a GUI called "DB Browser for SQlite" (sqlitebrowser).

First remove the foreign keys contraints check:

1. Click on "Edit Pragma"
2. Untick the "Foreign Keys" box

Now edit the foreign keys constraints of all the tables mentionned in this issue. Here I take the example of the incorrect foreign key of the cue table:

1. Select the table and click on "Modify a Table"

2. Enlarge the new window so you can see "Foreign keys", then double click on the foreign key you want to edit (here there's only one) and simply change the values (here from library_old to library)

Then, to modify the default value of the filetype field of the library table:

1. Select the library table and click on "Modify a Table"
2. Find the row mentionning filetype and the "Default" column
3. Double click on the "?" then delete it to leave an empty field.

Finally you can reactivate the foreign key pragma (BTW if you use the mixxxdb_cleanup.sql utility, you can now remove the PRAGMA foreign_keys = OFF; line):

1. Click on "Edit Pragma"
2. Tick the "Foreign Keys" box

Now you can save and close the database. And from now you're life will be very slightly better. :-)