[Typo3-dev] Nested Queries in MySQL wrapper class

[Rainer Kuhn]

Joel Faucett wrote:
>    How does one implement nested queries in the wrapper functions? e.g. 
> I want to get the 5 most recent items sorted by title, but the following 
> code returns an empty result.  Is it an SQL error that I'm not seeing or 
> have I structured it incorrectly?
> 
> $innerQuery = 'SELECT uid FROM tx_tekresearch_sum ORDER BY crdate DESC 
> LIMIT 5';
> $res = $GLOBALS['TYPO3_DB']->exec_SELECTquery(
>    '*',         // SELECT ...
>    'tx_tekresearch_sum',     // FROM ...
>    'uid IN ('.$innerQuery.')',    // WHERE...
>    '',            // GROUP BY...
>    'title',    // ORDER BY...
>    ''            // LIMIT ...
>    );

Hi Joel,

maybe this is the issue:
http://dev.mysql.com/doc/mysql/en/Subquery_errors.html


This means that statements of the following form will not work, although 
this happens only in some early versions, such as MySQL 4.1.1:

SELECT * FROM t1 WHERE s1 IN (SELECT s2 FROM t2 ORDER BY s1 LIMIT 1)

# Unsupported subquery syntax:
ERROR 1235 (ER_NOT_SUPPORTED_YET)
SQLSTATE = 42000
Message = "This version of MySQL doesn't yet support
'LIMIT & IN/ALL/ANY/SOME subquery'"

Cheers,
Rainer