👀 Views: 1 💬 Answers: 1 📅 Created: 2025-06-06

mysql stored-procedures php pdo PHP

I'm working with an scenario with a stored procedure in MySQL 8.0.23 that uses OUT parameters to return results. I have the following procedure that is supposed to return the total number of users and the count of active users: ```sql DELIMITER $$ CREATE PROCEDURE GetUserCounts(OUT totalUsers INT, OUT activeUsers INT) BEGIN SELECT COUNT(*) INTO totalUsers FROM users; SELECT COUNT(*) INTO activeUsers FROM users WHERE status = 'active'; END$$ DELIMITER ; ``` When I call this procedure from my PHP application, it executes without errors, but the OUT parameters seem to return null values: ```php $stmt = $pdo->prepare("CALL GetUserCounts(?, ?)"); $stmt->bindParam(1, $totalUsers, PDO::PARAM_INT | PDO::PARAM_INPUT_OUTPUT); $stmt->bindParam(2, $activeUsers, PDO::PARAM_INT | PDO::PARAM_INPUT_OUTPUT); $stmt->execute(); echo "Total Users: $totalUsers, Active Users: $activeUsers"; ``` However, when executing the above code, the output is: ``` Total Users: , Active Users: ``` I checked and the `users` table actually contains records, and I also tried hardcoding values in the stored procedure to see if I could get any output, but I still get null. I feel like I'm missing something about using OUT parameters correctly with stored procedures in MySQL. I've also tried using the `SELECT` statement directly without the procedure and it worked fine. Is there something specific about the OUT parameters in MySQL that I need to be aware of? Any help would be greatly appreciated! Is there a better approach?