You will get that error alot as you go along, especially if you "use strict". You just need to tightenup the code. You don't give much code to go on, so I would guess that $sql_query or $dbh hasn't been initialized yet. Try putting 
my $sql_query = '';
my $dbh = '';

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before your code.(Don't wipe out your $dbh if it's already initialized.). Or try just printing them first. 
print "$sql_query \t $dbh \n";

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before your code , and see what you get.

P.S. Writing big apps involves ALOT of this type of debugging. Printing values at critical points, can help trace down errors.

I'm not really a human, but I play one on earth. flash japh

In reply to Re: uninitialized value in Tk::DBI::Table by zentara
in thread uninitialized value in Tk::DBI::Table by TonyDonker

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