[TYPO3-dev] Use of subqueries

[Rik Willems]

Hi Martin,

Thank you for this, it is interesting information.

Greets, Rik

Martin Kutschker schreef:
> Rik Willems schrieb:
>> Hi Masi,
>>
>> What exactly do you mean with EXPLAIN?
> 
> Mysql will tell you how it executes a query if you put an EXPLAIN before it.
> 
> Fire up phpMyAdmin and execute for example this statement:
> 
> EXPLAIN SELECT * FROM pages p LEFT JOIN pages_language_overlay plo ON (p.uid=plo.pid)
> 
> EXPLAIN helps a lot to check if your queries and indices are efficient! Mysql may surprise you how
> it uses your indices and in what order it executes the joins.
> 
> See the Mysql docs for more information.
> 
> Masi