[TYPO3-core] RFC #13273: Bug: Caching framework sub-select is slow because mysql does not use indexes on outer query

[Xavier Perseguers]

Hi again,

If no "fit-all" solution is found, it's always possible to create some specialized method within t3lib_db that would do basically:

->deleteFromMultipleTables(...)

and implement it with some highly-efficient query within MySQL and other DBMS supporting those special queries and using subqueries for the other (Oracle for instance). This dispatch would take place 
within DBAL, in ux_t3lib_db...

The idea was already raised before we implemented it with subqueries.

-- 
Xavier Perseguers
http://xavier.perseguers.ch/en