How do you get the row returned by a SQL query that includes PREPARE and EXECUTE in PHP?

Question

How do you get the row returned by this SQL query using PHP:

SET @r := (SELECT ROUND(RAND() * (SELECT COUNT(*) FROM mytable)));
SET @sql := CONCAT('SELECT * FROM mytable LIMIT ', @r, ', 1');
PREPARE stmt1 FROM @sql;
EXECUTE stmt1;

Setting $query equal to the above and then doing the usual mysql_query($query) is not returning any results.

Answer 1

Do it like this to see if it works

mysql_query('SET @r := (SELECT ROUND(RAND() * (SELECT COUNT(*) FROM mytable)));');
mysql_query('SET @sql := CONCAT('SELECT * FROM mytable LIMIT ', @r, ', 1');');
$resource = mysql_query('PREPARE stmt1 FROM @sql;EXECUTE stmt1;');

Dont forget to escape the sql in the second instruction