Have you, as I was just now, been repeatedly confounded by PHP flat-out refusing to load its MySQL module on Windows? I have just finished banging my head against this particular wall for a day or so and would like to share the Apache Way to solving the issue.

The problem is, as is so frequently the case, DLL Hell. The php_mysql.dll module loads libmysql.dll, but apparently it has to be the version against which it was compiled. The required DLL is bundled with PHP, but what if an older, incompatible version of that DLL is found earlier in the search path? You’re hosed, that’s what if, and the module load fails with a message to the log file like so:

PHP Warning: PHP Startup: Unable to load dynamic library 'D:\\php-5.2.3\\ext\\php_mysql.dll' - The specified procedure could not be found.\r\n in Unknown line 0

I suppose that would be a missing symbol in the underlying library on other platforms. A quick Google put me on the right track and sure enough the indispensable Process Explorer utility tells me that httpd.exe has C:\WINDOWS\system32\libmysql.dll loaded. Yup, that’s our problem. No, I didn’t build that box. That box must have been built by someone who thought copying crap into the Windows directory is ever a good idea.

How do we solve this the Apache Way? Not by copying DLLs around, that’s for sure. The Apache configuration language has the LoadFile directive for this particular purpose. Loading the correct DLL right before the PHP module:

LoadFile "d:/php-5.2.3/libmysql.dll"
LoadModule php5_module "d:/php-5.2.3/php5apache2_2.dll"


makes PHP pick up the right symbols to run with MySQL.