Hi, I am having a devilishly difficult time running a piece of SQL code that runs without a problem in MySQL but produces an error when executed by Perl. The SQL fragment in question is: 
SET @num :=  0;
SET @id  := -1;

SELECT e.*, y.ChallengerID, CASE WHEN ep.isChampion IS TRUE THEN TRUE 
+ELSE FALSE END AS isCurrentChampion
FROM
(
.
.
.

[download]
And the error is: 
DBD::mysql::st execute failed: You have an error in your SQL syntax; c
+heck the manual that corresponds to your MySQL server version for the
+ right syntax to use near 'SET @id  := -1;

SELECT e.*, y.ChallengerID, CASE WHEN ep.isChampion IS TRUE THE' at li
+ne 2

[download]
The query executes without a problem in MySQL. I do not know why put placing the execution of the SET statement directly into the Perl code using \@ seems to result in something that works. In this case, I removed the SET statement from the code.sql file but left the remainder of the SQL code in place... 
#!/usr/bin/env perl

use strict;
use warnings;

use DBI;
use Data::Dumper;

# MYSQL CONFIG VARIABLES
my $host = "XYZ";
my $db = "XYZ";
my $dbuser = "XYZ";
my $dbpw = "XYZ";

# CONNECT TO MYSQL
my $dbh = DBI->connect("DBI:mysql:$db", $dbuser, $dbpw) || die "Could 
+not connect to database: $DBI::errstr";
my $myquery;

$myquery = "SET \@num := 0, \@id := -1;";
my $sth = $dbh->prepare($myquery);
$sth->execute();

# Retrieve all open tests
my $file = "../sql/code.sql";
{
  local $/ = undef;
  open FILE, $file or die "Couldn't open file: $!";
  $myquery = <FILE>;
  close FILE;
}

print "\nSQL scheduling query constructed... executing...";           
+ 
$sth = $dbh->prepare($myquery);
$sth->execute();

[download]

In reply to DBD and a MySQL query with a SET @num line by edieguez

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