in data base testing we will chech whether the information or any contents we are adding going correctly in the database or not,we also want to know whether there is any memory leak,, for full information u can visit...http:\\roublesodhi.googlepages.com
I don't think so that there is some correlation between Database & Memory leak as per my understanding as it is associated with OS only.
Memory leak is a particular kind of unintentional memory consumption by a computer program where the program fails to release memory when no longer needed. This condition is normally the result of a bug in a program that prevents it from freeing up memory that it no longer needs.
and to test this we havee number of tools in the market...
you can test many things related to DB but the main part you should test is inserting ASCII characters. your DB should be Unicode supported if the application supports multi language. Also i believe it is important to test DB backup and Restore to check if nothing get lost during backup.
It all depend what sort of application or DB you are using and what sort of functions you are testing but in my opinion above should be test with almost all DB.