[Typo3-dev] DBAL Drivers

[Florian Schaeffer]

Hello Martin,

> - how can i figure whether my sql code is dbal proof ... becaues 
> currently ist is possible to use mysql specific functions in select and 
> where clauses
> 
> as an examlple i'm currently using the |FIND_IN_SET() function in a 
> where clause ... how du i figure out whether the dbal supports this. 
> depending on the result i could decide to use a workaround or to create 
> an extension für mysql only. |

Only use standard-sql functions and avoid any DB-specific things like 
the FIND_IN_SET or LIMIT BY - things.

I don't know the DBAL at the moment but in ADODb there are 
meta-functions for that, so one can use a wrapper for let's say the 
limit part of the query.

In ADODb you would write $conn->selectLimit and ADODb builds a suitable 
command for the selected DB. (Oracle uses numrows, MySQL LIMIT ad so on)

So use the meta-functions provided in class.t3lib_db.php 
(exec_SELECTquery, exec_SELECT_mm_query for multiple tables and so on)

*Don't use* exec_SELECTquery('my own specific to_char() 
oracle-convert-function').

So simplay said, stick on old SQL-functions every DB is capable of or 
use (if available) meta-functions.

Karsten knows more about the DBAL, so we should wait until everything is 
finished and I think there will be a documentation or at least a 
how-to-archive-dbal-functionality document ?

HTH
Florian