Read the next section to learn more about what you may be missing. Explanation of the packages the shell script tests for Perl is definitely required. Make is a standard program used to simplify compiling new programs. DBI and DBD both use Make as part of the compiling process. You must have this.
Kernel headers are structures and constants needed for compiling most standard programs.
You very likely need this. EGCS is the C compiler supplied with Red Hat Linux 6.0. The compiler turns human-readable code into an executable program. If you don't have the EGCS package installed, perhaps you have another C compiler installed instead. You don't have to have EGCS, but you do need a C compiler.