Hello Monks. I would like to use a variable "$columns" to describe the columns I wish to extract. Perl will not allow me to store, for example, $column = "sid = $row->{sid}"; because it demands that I declare $row

I have pasted the troublesome code below. Thank you, in advance for your perls!

use strict;
use warnings;
use Text::CSV;
use DBI;
use Data::Dumper;
  
# Connect to the database, (the directory containing our csv file(s))
my $dbh = DBI->connect ("dbi:CSV:", undef, undef, {
      f_dir                       => ".",
      f_ext                       => ".csv",
      f_encoding                  => "utf-8",
      RaiseError                => 1,
      }) or die $DBI::errstr;

  
# Output using sql query
my $query = (qq(select * from newCsv.csv WHERE gender ='male' AND geno
+type ='a' ));
# my $columns = "sid = $row->{sid} \tgender = $row->{gender}\n"; # per
+l is seeking declaration of $row
my $queryResult;
my $sth = $dbh->prepare($query);
$sth->execute;

while (my $row = $sth->fetchrow_hashref) {
my $col= "sid = $row->{sid} \tgender = $row->{gender}\n";  # cannot ch
+ange this to my $col=$columns
$queryResult = $queryResult.$col; 
}    

$sth->finish();
$dbh->disconnect(); 
print "Result \n\n$queryResult";

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In reply to DBI::CSV using a variable to request columns by Sandy_Bio_Perl

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