[TYPO3-core] RFC #13945: Bug: Missing key on l18n parent in tt_content table

[Martin Kutschker]

Dmitry Dulepov schrieb:
> Hi!
> 
> Christian Kuhn wrote:
>> Problem:
>> t3lib_BEfunc::translationCount issues a query like 'SELECT COUNT(*) FROM
>> tt_content WHERE l18n_parent=123 AND sys_language_uid!=0 AND deleted=0'.
>> EXPLAIN shows no usable key for this type of query.
>>
>> Solution:
>> Add key on l18n_parent.
> 
> Have you tried a composite key instead of a single field key? Composite
> keys often give better results.

Like "l18n_parent (l18n_parent,sys_language_uid,deleted)"?

In theory Mysql wouldn't need to read any row of the table.

Masi