I have a query like this

set @valid_total:=0;
set @invalid_total:=0;
select week as weekno, measured_week,project_id as project, 
role_category_id as role_category,
valid_count,valid_tickets,
(@valid_total := @valid_total + valid_count) as valid_total, 
invalid_count,invalid_tickets, 
(@invalid_total := @invalid_total + invalid_count) as invalid_total
from metric_fault_bug_project 
where measured_week = yearweek(curdate())
and role_category_id = 1 and project_id = 11;

it executes fine in heidi (MySQL client) but when it comes to perl, it gives me this error

DBD::mysql::st execute failed: You have an error in your SQL syntax; check the m
anual that corresponds to your MySQL server version for the right syntax to use
near ':=0;
                                set :=0;
                                select week as weekno, measured_week,project_id
as project' at line 1 at D:\Mx\scripts\test.pl line 35.
Can't execute SQL statement: You have an error in your SQL syntax; check the man
ual that corresponds to your MySQL server version for the right syntax to use ne
ar ':=0;
                                set :=0;
                                select week as weekno, measured_week,project_id
as project' at line 1

The problem seem to be in the set @valid_total := 0; line.

I am fairly new to Perl. Can anyone help?

this is the complete perl code

#!/usr/bin/perl

#use lib '/x01/home/kalpag/libs';


use DBI;
use strict;
use warnings;

my $sid = 'issues';
my $user = 'root';
my $passwd = 'kalpa';
my $connection = "DBI:mysql:database=$sid;host=localhost";


my $dbhh = DBI->connect( $connection, $user, $passwd) ||
            die "Database connection not made: $DBI::errstr";


my $sql_query = 'set @valid_total:=0;
         set @invalid_total:=0;
         select week as weekno, measured_week,project_id, 
                 role_category_id as role_category,
         valid_count,valid_tickets,
             (@valid_total := @valid_total + valid_count) as valid_total, 
                 invalid_count,invalid_tickets, 
         (@invalid_total := @invalid_total + invalid_count) as invalid_total
         from metric_fault_bug_project 
         where measured_week = yearweek(curdate())
         and role_category_id = 1 and project_id = 11';

 my $sth = $dbhh->prepare($sql_query) or die "Can't prepare SQL statement:     $DBI::errstr\n";

 $sth->execute() or die "Can't execute SQL statement: $DBI::errstr\n";

while ( my @memory = $sth->fetchrow() )
{
            print "@memory \n";
}