Consider replacing the hash of start/end dates with YEAR(date) and MONTH(date)functions.

#!/usr/bin/perl
use DBI;
use strict;

my $sql =<< "SQL";
  SELECT distinct FID_CUST 
  FROM session 
  WHERE YEAR(DAT_END) = ? AND MONTH(DAT_END) = ?
SQL

my $dbh = get_dbh();
my $sth = $dbh->prepare($sql);    

my $year = 2017;    
for my $mth (1..9) {   
  print "$year-$mth\n";
  $sth->execute($year,$mth);   
  while (my ($fid_cust)= $sth->fetchrow_array ){
    print "$fid_cust\n";
  }
  $sth->finish();
}
$dbh->disconnect;


# connect
sub get_dbh{
  my $database = "xxx"; my $user = "xxx"; my $pw = "xxx";
  my $dsn = "dbi:DB2:$database"; 
  my $dbh = DBI->connect($dsn, $user, $pw, 
     { RaiseError=>1, AutoCommit=>1 } )
     or die "Could not connect to database :".DBI->errstr;
  return $dbh;
}

[download]
poj

In reply to Re: Code flow not going to while loop by poj
in thread Code flow not going to while loop by dipit

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