[egenix-users] Problems with number of results being returned

[Charlie Clark]

Am 05.04.2007, 20:28 Uhr, schrieb Dev Sen <DEV.K.SEN at saic.com>:

> Hi,
> This is my first post to the list, so I hope my question isn¹t too naïve.
> I am developing a database app in Zope/Plone using MySQL with the egenix  
> DB
> adaptor on a Mac Pro. So far everything with the adaptor has been good,
> although I am now having strange issues. I have some queries which return
> around 5,000 rows of data. When I run the query with parameters so that  
> only
> 1200 or so rows are returned there is no problem, however, for larger  
> result
> sets I get an error saying the connection to the database was lost.  
> Another
> developer working on the same project (identical code, software versions)
> but running Windows XP doesn¹t have this problem at all. Also, running  
> the
> queries directly in MySQL works fine. Therefore we think it has  
> something to
> do with the Mac OSX version of the egenix DB adaptor.
> Has anyone seen this behavior before? Is this a known bug?

Dev,

I believe that MySQL has only just released their ODBC driver for Mac OS X  
and this is where we suspect the problem is so it's probably a good idea  
to make sure you have the most uptodate version of this driver. As for  
limiting the number of rows returned. Are you doing this through the  
advanced tab in the ZSQL method or through LIMIT in the SQL statement?  
MySQL (MyASM tables) can be unbelievably slow on certain types of query  
such as ANSI INNER JOINS or subselects but if you enforce a hard LIMIT in  
your SQL there should be no reason for a timeout as maybe happening here.

Charlie Clark

-- 
Charlie Clark
eGenix.com

Professional Python Services directly from the Source
>>> Python/Zope Consulting and Support ...        http://www.egenix.com/
>>> mxODBC.Zope.Database.Adapter ...             http://zope.egenix.com/
>>> mxODBC, mxDateTime, mxTextTools ...        http://python.egenix.com/
________________________________________________________________________

:::: Try mxODBC.Zope.DA for Windows,Linux,Solaris,MacOSX for free ! ::::



    eGenix.com Software, Skills and Services GmbH  Pastor-Loeh-Str.48
     D-40764 Langenfeld, Germany. CEO Dipl.-Math. Marc-Andre Lemburg
            Registered at Amtsgericht Duesseldorf: HRB 46611