It would help if you told us what you were seeing as a problem. Also, things like what version of Perl, what OS, and what the basic purpose of what you're doing ...

The most obvious problem I'm seeing is that $sql is defined well after any time you use it.

A few helpful pointers:

• use strict and warnings. They will help catch a number of silly errors/typos that a human cannot see.
• Try using print as a debugging tool. I notice you use $sql a lot. Are you sure you know what its value is at any given point?

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