MySQL Stored Procedure Empty in PHP works in PHPMyAdmin - php

Question

I have the following stored procedure. It works fine in phpMyAdmin, but when I try to run it using PHP PDO library I get no errors, just an empty array.
CREATE DEFINER=`root`#`localhost`
PROCEDURE `get_gauge_values`(IN `maxdate` TIMESTAMP,
IN `dashboard_id` INT)
begin
DECLARE finished BOOLEAN;
DECLARE line_timestamp TIMESTAMP;
DECLARE line_tagid INT;
DECLARE line_name VARCHAR(50);
DECLARE line_value VARCHAR(50);
DECLARE cid CURSOR FOR
SELECT Max(hd.timestamp),
hd.tag_id
FROM dashboard_to_dashboard_lines ddl
JOIN dashboard_lines dl
ON dl.line_id = ddl.dashboard_line_id
JOIN historical_data hd
ON hd.tag_id = dl.gauge_tag_id
WHERE hd.timestamp <= maxdate
AND ( dashboard_id = 0
OR ddl.dashboard_id = dashboard_id )
GROUP BY 2;
DECLARE CONTINUE handler
FOR NOT found
SET finished=TRUE;
SET finished=FALSE;
DROP TABLE IF EXISTS gauge_values_temp;
CREATE TABLE gauge_values_temp
(
name VARCHAR(255),
value VARCHAR(50)
);
open cid;
START_LOOP:
LOOP
FETCH cid INTO line_timestamp, line_tagid;
IF finished <> false THEN
LEAVE start_loop;
ELSE
INSERT INTO gauge_values_temp
(name,
value)
SELECT ol.name,
hd.value
FROM dashboard_lines dl
JOIN operation_lines ol
ON ol.line_id = dl.line_id
JOIN historical_data hd
ON hd.tag_id = dl.gauge_tag_id
WHERE dl.gauge_tag_id = line_tagid
AND hd.timestamp = line_timestamp;
end IF;
end LOOP;
close cid;
SELECT *
FROM gauge_values_temp;
end
The code that I use in PHP for trying to pull data back is the following:
try {
$sql = "CALL get_gauge_values('2015-12-28 09:00:00','1')";
$q = $link->query($sql);
$q->setFetchMode(PDO::FETCH_ASSOC);
} catch (PDOException $pe) {
die("Error occurred:" . $pe->getMessage());
}
while ($r = $q->fetch()) {
echo 'Row returned<br />';
}
exit;
I'm confused as to why it returns the result set in phpMyAdmin but running it with the PHP code below in a browser returns 0 rows. All I get when I print_r($q) is Array( )...