It’s been a while since our last schema change release in May 2017. To move forward on some features we’d like to add, we plan to have a Spring 2019 schema change release set for May 13th, 2019. This release should not be disruptive to downstream users, as we plan only to augment the schema with some new tables and columns, and not break any of the existing schema.
Here’s our list of tickets for the Spring 2019 schema change, with descriptions of what’s being changed:
MBS-1658: Add a free text field to collection items. This change will allow users of collections to annotate each item with free text, to hold personalized info about the item (for example, that a release is of a specific pressing, was purchased in 1999 at the Village Discount, or was a gift from your mom). This ticket will add a new TEXT column to editor_collection_release and all other entity-specific editor_collection_* tables. It will not add any new tables or modify any existing columns.
MBS-5387: Mark artist credits as having pending edits when they’re being edited. On an artist’s aliases tab, we provide the ability to directly edit artist credits associated with that artist. However, doing so doesn’t indicate anywhere that the artist credits are being changed (we typically highlight entities with pending edits). To resolve this, we’ll be adding an INTEGER edits_pending column to the artist_credit table. This ticket will not change any existing columns of the artist_credit or artist_credit_name tables.
MBS-5818: Make it possible to have ordered collections. Editor’s collections of entities are automatically ordered by field, for example, releases in collection are ordered by ascending release date. Sometimes, one might want to order collector’s items by other criteria, for example, most wanted releases. This change will enable editors to order collection items by hand if they want to. To do so, an INTEGER position column will be added to the editor_collection_* tables.
MBS-7480: Store cover art image file sizes. Knowing file sizes for cover images and their thumbnails would allow us to better detect when a thumbnail isn’t available, and also allow us to display file sizes to the user before they download an image. To do this, we’ll add four INTEGER columns to the cover_art_archive.cover_art table to store the file sizes in bytes: filesize, thumb_250_filesize, thumb_500_filesize, thumb_1200_filesize.
MBS-9428: Allow multiple users to share one collection. In some cases (like a collection of cleaned up entities several people want to keep an eye on, or a radio station’s collection of vinyl the station owns), it would be quite useful if multiple editors could add (and remove) entries from a collection. This would make cooperation easier and hopefully make community projects (such as the Composer Diversity Database project) easier to start and work on. We’ll add an editor_collection_collaborator table linking collections to the editors allowed to make changes in them (only the collection owner will be able to make changes to the list of allowed collaborators).
MBS-9491: Move hard-coded genres to a database table. We recently added genres to MusicBrainz, but they’re currently stored as an object in the server code. This change will move them to a new table genre (id, gid, name, comment).
MBS-10062: Add aliases for genres. Connected to the previous issue, we need a way to be able to specify “hiphop”, “hip hop” and “hip-hop” are all the same thing, and eventually to store translated versions of genres. This will add a table genre_alias (id, genre, name, locale, edits_pending, last_updated, primary_for_locale).
MBS-9973: Add a date added column for collection items. Editor’s collections have no editing history, thus it doesn’t allow to sort items by date of addition to the collection they belongs to. To allow this, editor_collection_* tables will get a TIMESTAMP added column.
MBS-10052: Add new tables for the event poster archive. This will move us another step toward CAA-84, giving us a place to store event posters, logos, and other related images. The schema change here will be to add a new event_art_archive schema, detailed in the comments in MBS-10052. There will be no change to the existing cover_art_archive schema.
The following tickets will also be included, but only involve adding some missing foreign keys, triggers, and constraints to standalone mirrors; these will not be created and have no effect on replicated mirrors.
MBS-9365: Adds a missing foreign key between the event_meta and event tables.
MBS-9462: Adds some missing l_event_url triggers to delete unused URLs.
MBS-9664: Adds constraints to prevent an entity from linking to itself in a relationship.
If you have any questions, please do leave a comment below or on the linked JIRA tickets!
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