Something you can do to make your code easier to read (beyond the formating in this forum) is to use q() and qq(). For example, where you do this: 

$INSERT_SQL="INSERT INTO trg_table(".
"column1,".              
"column2".                  
") VALUES ".
"(?,".
"?)";

[download]
Try this instead: 
$INSERT_SQL= q{
INSERT INTO trg_table( column1, column2 )
 VALUES (?,?)
};

[download]

Because you do not need variable interpolation here, you can use single quotes. If you need to do variable interpolation, use qq() instead.

Ivan Heffner
Sr. Software Engineer, DAS Lead
WhitePages.com, Inc.

In reply to off-topic: using q() and qq() to improve readability by Codon
in thread how to use place holders? by Anonymous Monk

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