First off, forgive me if this is a schoolboy question 🙂
We have a number of applications that user Delphi dbxpress to access a MySQL 5 server. These applications were all written on Delphi 2007 against a libmysql.dll version 5.0.xx (actual version forgotten)
This dll has been distributed to all users and is working fine.
I have just upgraded to Delphi 2010 and discovered that that needs to user libmysql 5.1.xx to see MySQL servers.
Trouble is, if I replace the 5.0.xx libmysql with the newer one, existing applications will not startup. On the flip side Delphi 2010 will not work with the older dll.
Whilst I can get both versions of the IDE (2007 and 2010) to work with the database by placing the appropriate dll versions in the \bin folder of the application, this doesn’t solve the problem for the users.
Any suggestions on how I can get the applications to look for the appropriate version of the dll.
We were hoping to not have to move all our applications to Delphi 2010 immediately…
There are several methods: check Dynamic-Link Library Search Order and Dynamic-Link Library Redirection.
The safest one is to put the DLLs you need in the application executable folder, because it’s the first one checked. Given today’s disk size, it may not be a disk space problem. The DLL may also be not share among processes, but that could not be an issue too.