Support aliases with QQ

[VexedPanda]

Right now, there's no way in QQ to accomplish the following query without using SubSQL:

select u.* from users as u
left join project_user_assn as pu1 on pu1.user_id = u.id
left join project_user_assn as pu2 on pu2.user_id = u.id
where
pu1.project_id = 1
and 
pu2.project_id = 2

Perhaps syntax like this?

QQ::AndCondition(
QQ::Equal(QQ::Alias(QQN::User(), Projects, 'pu1')->ProjectId, 1),
QQ::Equal(QQ::Alias(QQN::User(), Projects, 'pu2')->ProjectId, 2)
)

QQ::Alias would simply return a QQNode, so the rest of the code would be unchanged, it would just be smart enough to realize that the pu1 alias and the pu2 alias should result in different aliases for the join (QQN::User() to QQN::User()->Projects) passed in.

[VexedPanda]

Progress is being made. Moving to 1.2.

[VexedPanda]

Here's a working patch

[VexedPanda]

So the downside to this approach is that I basically had to copy/paste GetColumnAliasHelper? from the three base QQNode types (QQNode, QQAssociationNode, and QQReverseReferenceNode), leading to a lot of code duplication.

I'll try another approach and see if it's cleaner.

That said, this seems to work beautifully. :)

[VexedPanda]

Ok, here's option two. I think this is a lot cleaner, and so far seems just as solid. We should make some test cases and example code. :)

[VexedPanda]

Syntax for both options is:

User::QueryArray(
  QQ::AndCondition(
    QQ::Equal(QQ::Alias(QQN::User()->Projects, 'pu1')->ProjectId, 1),
    QQ::Equal(QQ::Alias(QQN::User()->Projects, 'pu2')->ProjectId, 2)
  )
);

This will return a list of all users who are in both project 1 and 2.

[alex94040]

Vexed - do you want to write up an example, and I'll do the unit tests?

[VexedPanda]

Sure. I should have time for that tomorrow. :)

[VexedPanda]

Here's an example. Same as above.

[VexedPanda]

Any feedback / tests on this?

[alex94040]

So sorry, I have been slacking. Difficult personal time for me this past month (and will be most of next month). I'm buying a house, and it's a huge pain in the rear. But I will come back and take care of this!

[VexedPanda]

Sorry, definitely didn't mean to sound accusitory. :)
That's great! Congratulations! I bought my first house about a year and a half ago, and it was pretty stressful, so I know what that's about. :)

[alex94040]

New combined patch. Includes code, examples, and tests

[alex94040]

OK, so here's a combined patch. Summary:
1) No code modifications
2) Expanded the example a little bit - added another, slightly more complex, instance of QQ::Alias() use.
3) Wrote new tests for QQAlias.
4) Refactored some of the shared functionality between the new tests and what we had in ExpandAsArray? tests into the base QCubed Unit Test Case class.

Please review! Let's remember to commit this to both 1.1 and 2.0.

[VexedPanda]

I didn't re-check the alias code, but the new example and test code looks great. :)

[VexedPanda]

Any word on this? If it's ready to commit, I think it'd be a great new feature for 2.0.1. :)

[alex94040]

I think this is ready to commit.

[VexedPanda]

(In [914]) Fixes #321

[VexedPanda]

(In [915]) Fixes #321 for v2.0.1