From the devil's mouth:
MSDN
Better yet a google search: Google search for odbc security
In perl try dbi
Security in DBI thread: Read the whole thread.
And a google search: Google search on dbi security
But where is the perl???

In a general note securing databases have different methods. When you automate a database connection the automation opens up some possible places for exploits. Always scope the processes and related id's in what they need to do and limit access accordingly. Limit the connections on an IP basis if possible. But that discussion is in itself maybe best for other areas.