Decided by http://scheduling.ocharles.org.uk/results and http://chatlogs.musicbrainz.org/musicbrainz-devel/2011/2011-12/2011-12-05.html

Added schema change component.

I'm already assigned, so here's what this should look like: there are four things that matter for a timeline event: date, title, description, link. I propose a new table should be added for timeline events, with date as a primary key (it doesn't work with the graph if there's more than one per date anyway), unless the other devs want a surrogate key of some sort.

Once the table exists, the timeline-graph code can be migrated to use it, and the existing events put into the table.

This ticket is under consideration for the May 15h schema change release. Please do the following:

• Specify exactly what the user interface changes will be. Mock ups would be great. Due date: April 2
• Specify exactly what the database changes will be. We will need to have an exact database table change proposal. Exactly which columns will be added/removed/modified and what new tables will be created. If you cannot specify the changes to be done, chase down a developer to specify them for you. Due date: March 26

• There are no user interface changes for this ticket; the timeline graph should not change in appearance or function due to this change. The only exception is that where multiple events currently are on the same date (which makes one or the other inaccessible, so is a current bug) they should be merged; this is not a schema-change problem though. (This only applies to June 30, 2003 and May 9, 2004)
• CREATE TABLE timeline_event(event_date date primary key, title varchar(100) not null, description text not null, link varchar(255) not null); unless ocharles or warp thinks event_date shouldn't be the primary key for some reason (it is certainly the only thing that needs an index, or that lookups will be done by), or if they disagree with my varchar length choices.

This looks good, but does it belong in the MusicBrainz schema? Maybe we should introduce a statistics schema?

I don't care one way or the other; I'll leave that decision to you folks who care about the schema more. If a new schema is introduced, I'd recommend moving the 'statistic' table as well (but I'm sure you knew that).

I'd rather not introduce a new schema, because it complicates tables export/import and live data feed (the 'statistic' table is a replicated table, as should probably be the new 'timeline_event' table).

Rob's comment said this is under consideration for the May 5th schema change, but it was in the wrong fix version. As there are no other comments, I'm moving it to the May 5th fix version.

In review at http://codereview.musicbrainz.org/r/1876/diff/#index_header