[TYPO3-core] RFC: Bug #11903: Use separate tables for tags in the caching framework

[Martin Kutschker]

Oliver Hader schrieb:
> Hi Masi,
> 
> Martin Kutschker schrieb:
>> Oliver Hader schrieb:
>>> Hi Steffen,
>>>
>>> Steffen Kamper schrieb:
>>>> Hi olly,
>>>>
>>>> following notes:
>>>> * unit tests doesn't work, 6 failures in testsuite
>>> Ok, I fixed them to work with again... however, they are not complete.
>>>
>>>> While testing, the writing works as expected.
>>>> Clearing cache does the clearing, but i get a MySQL error:
>>>>
>>>> ['lastBuiltQuery'] =>
>>>> 'TRUNCATE '
>>>> ....
>>> That happens when no tagsTable is set. And it would have happened if not
>>> cacheTable was set. It's now checked in the contructor.
>>>
>>> Attached is a new version with these changes:
>>> * fixed bug in garbage collector concerning removal of entries without tags
>>> * added contructor check for cacheTable and tagsTable
>>> * modified unit tests
>> I know that the patch is in but yet a -1 from me. Why? Because the patch sneaks in a new feature of
>> t3lib_db. This should have been a separate RFC. The reason is that the new feature
>> DELETEmultipleTablesQuery() isn't DBAL save.
>>
>> This surprises me as I have attached many notes in the bug tracker concerning other database
>> systems.  I suggest to use two different WHERE clauses: one for the JOIN and one for WHERE clause.
> 
> 
> Yes, that's the information I pointed out in the "Notes:" section of
> this RFC. There is no overall solution for all DMBS right know and I
> discussed this also in private with Xavier as DBAL team leader.

Oh. To me the conclusio (of my own research) was, that having such a feature is possible, but it
must be implemented differently for all database systems.


> Your example would only delete elements from one table.

Ouch. I thought that the point was the join, not the deleting from multiple tables at once. Mysql
offers both options, but I haven't checked properly for both options. I'll reinvestigate that matter.

Masi