It sounds like you're using the DBI RaiseError attribute to have the DBI method calls die on error, then trapping the die with eval and doing your own error handling. If that's the case, you should just turn off RaiseError, check the return value from prepare and execute, and get the message from $DBI::errstr if there's an error.

Anyway, as merlyn said, you've been misinformed about the performance penalty of eval. eval BLOCK does not have a performance penalty, but eval EXPR has a performance penalty every time it is executed (i.e. using eval EXPR in a loop is very inefficient).