php - Executing mysqli prepared statment within while loop that's within another while loop

one text

Solution:

stmt->store_result() can not run before stmt->execute().

$stmtUsers = $conn->prepare("SELECT username, setting1 FROM Users");
if ($stmtUsers->execute() === FALSE) {
    die("Could not execute prepared statement");
} else {
    $stmtUsers->store_result();                // After execute()
    $stmtUsers->bind_result($user, $setting1);
    while ($stmtUsers->fetch()) {
        /* Check if each user has setting 1 disabled */
        if ($setting1 == '0'){
            /* Check if any alerts exist for each user */
            $stmtUsersAlerts = $conn->prepare("SELECT name, filter, email FROM Alerts WHERE user='".$user."' AND type='1'");
            $stmtUsersAlerts->execute();        // This line was missing
            $stmtUsersAlerts->store_result();
            $stmtUsersAlerts->bind_result($name, $filter, $email);
            while ($stmtUsersAlerts->fetch()) {
                /* Send email */
            }
            $stmtUsersAlerts->close();
        }
    }
    $stmtUsers->close();
}

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