PackageUpload* table subclassing must be fixed

[Mark Shuttleworth]

We have a standard way to deal with slightly polymorphic objects, and that is to make tables that can accommodate all variants and leave some fields NULL'able.

The PackageUpload, PackageUploadBuild, PackageUploadSource and PackageUploadCustom tables should please all be collapsed into PackageUpload.

This will greatly simplify code like PackageUpload.getQueueItems!

[Stuart Bishop (stub)]

I'm committing a database patch to database/schema/pending/stub-distroreleasequeue.sql that adds this as well as the refactoring requested in Bug #36472.

[Celso Providelo (cprov)]

When the code is fixed we also need to rename queue.py to respect the current domain name (distroreleasequeue.py).
The stub DB patch looks ok and migrates the previous data correctly.

[Malcolm Cleaton (malcolmcleaton)]

This isn't a case of a slightly polymorphic object in quite that way - sometimes a single DistroReleaseQueue row is related to more than one DistroReleaseQueueCustom row.

It's quite possible that this design is not optimum and that we can simplify it, but we can't do this simply by collapsing the tables and making the implied trivial code changes.

[Mark Shuttleworth (sabdfl)]

Nonetheless, the current design is inadequate and we do need to address
it. I look forward to a landing that cleans it up!

[Robert Collins (lifeless)]

The schema has been significantly refactored - DistroReleaseQueue no longer exists. I believe the polymorphism was resolved during that refactoring.

[Julian Edwards (julian-edwards)]

It wasn't fixed, DistroReleaseQueue was simply renamed to PackageUpload.

[William Grant (wgrant)]

However, I still don't think this is a bug. We often have many PackageUploadBuilds and a PackageUploadSource in a single PackageUpload.

[Julian Edwards (julian-edwards)]

On Wednesday 21 September 2011 12:35:58 you wrote:
> However, I still don't think this is a bug. We often have many
> PackageUploadBuilds and a PackageUploadSource in a single PackageUpload.

There is still a lot of opportunity for refactoring here, and as you note
PackageUploadSource is redundant. Reducing the number of tables generally
makes for quicker queries too.