How can you in a procedure function in mysql check if the cursor returns

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Asked: May 27, 20262026-05-27T21:00:58+00:00 2026-05-27T21:00:58+00:00

How can you in a procedure function in mysql check if the cursor returns

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How can you in a procedure function in mysql check if the cursor returns anything?

Is it possible to avoid doing the IF (SELECT COUNT(*) FROM stock ... and instead check up on the _cur variable somehow?

procedure function

DELIMITER $$

DROP FUNCTION IF EXISTS `stock_first_available_id` $$
CREATE DEFINER=`dynaccount`@`localhost` FUNCTION `stock_first_available_id`(_running_total_limit INT, _product_id INT, _group_id INT) RETURNS INT
BEGIN
    DECLARE _running_count INT default 0;
    DECLARE _id INT;
    DECLARE _current_id INT;
    DECLARE _sum_count INT;
    DECLARE _cur CURSOR FOR SELECT id, count FROM stock WHERE group_id=_group_id && type=2 && product_id=_product_id ORDER BY time DESC, id DESC;
    
    IF (SELECT COUNT(*) FROM stock WHERE group_id=_group_id && type=2 && product_id=_product_id) = 0 THEN
        RETURN 0;
    END IF;
    
    OPEN _cur;
    
    read_loop: LOOP
        FETCH _cur INTO _id, _sum_count;
        
        SET _running_count = _running_count + _sum_count;
        SET _current_id = _id;
        
        IF _running_count > _running_total_limit THEN
            LEAVE read_loop;
        END IF;
    END LOOP read_loop;
    
    CLOSE _cur;
    
    RETURN _current_id;
END $$

DELIMITER ;