Hello,
Please, could you tell us which are the old and new version of your SQL Server driver for PHP ?
Please, could you tell us whether this 25% degradation is general or only for some operations ( open of connections, queries,...) ?
Which is the full version (2000,2005,2008,2008 R2, 2012) and Edition (MSDE,Express,Web,Workgroup,Standard,...) of your SQL Server ?
We are waiting for your feedback to try to help you more efficiently and for that, i hope that you will understand that we need more informations.
Have a nice day
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