Issue #135: CActiveRecord::count() respects group and having

[klimov-paul]

Fixes #135
Now "CActiveRecord::count()" respects group and having.
Unit tests for "CActiveRecord" has been updated. Tests have been passed successfully.

[samdark]

Was it tested with non-MySQL? Especially SQLite.

[klimov-paul]

Test case "CActiveRecordTest" uses SQLite memory connection (line 19).

[klimov-paul]

This pull request adds logic from "CDbCommandBuilder::createCountCommand()" to "CActiveFinder::count()".

[samdark]

Looks OK for me.

@yiisoft/core-developers any comments?

[qiangxue]

This could potentially break BC.
Also, it is not semantically right if you do count with GROUP BY because you end up with returning the first count.

[klimov-paul]

In this fix I perform the count via sub query, which means count of the result of other query.
Group by will not affect the count result anyhow.
Also I can not see how this can break a BC, @qiangxue please provide an example of what exaclty you aware.

Actually the solution I suggest just copies the approach of "CDbCommandBuilder::createCountCommand()". Back there none has any complains.

[qiangxue]

By BC, I mean users' existing code may rely on the fact that group-by/having is ignored in the old code.
Since you are copying the code from CDbCommandBuilder::createCountCommand(), this probably isn't a big concern then.

[klimov-paul]

As for BC: may be you should tell @zhongjq and @alexandernst the issue they request actually breaks a BC and just close the issue #135.

[samdark]

I think we should try merging it for the next RC.

[acorncom]

It seems like most people who want group by/having to work with their code show up here to report bugs :-) There are regular reports of problems. Having it actually fixed and then clearly documented as one of the more major fixes would eliminate the BC concern, wouldn't it?

[samdark]

Should be OK but we definitely need to mention it in the UPGRADE.

[samdark]

0eec059

[samdark]

Thanks for working on this one.

[simontong]

You forgot to add the params (bindParams()) to the criteria

[klimov-paul]

@simontong, it is already done by #2230