hi

I am new to perl and would appreciate some pointers on how to improve my db access code. I have some code below to get all rows from a table, select their value for a particular column and then delete any other rows that have that value. I know i could use a more efficient sql query but the more effient query was really slow and this is faster. I was wondering how i should improve my db access code: 

   my $sql_select = "select * from $tableName";

     my $sth = $db->do($str_select);

        $sql_delete = "delete from $tableName where LiftChr=? and Lift
+Pos=?";

     my $sth1 = $db->prepare($sql_delete);

      while ($snp = $sth->fetchrow_hashref) {

          $sth1->execute($sql_delete, undef, $snp->{'LiftChr'}, $snp->
+{'LiftPos'});
    }

[download]
I was also wondering if there were any problems with getting more than one statement handler off the same database connection?

How would i add an 'or die' clause to the select statement when i want to get a statement handler off it? thanks in advance

In reply to cleaning up dbi code by Anonymous Monk

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