插入或使用MySQL觸發

Question

我有兩個MySQL表更新一行：sms和consumption。 sms表包含所有事務，而consumption表包含消耗的短消息的總和。

我的目標是能夠到現在的實際消費了一天，所以我只需要直接在consumption表檢查。 對於它，我試圖創建一個觸發器，它會驗證：

1. 如果1天沒有行consumption表，然後插入新行
2. 是否已經有日間行1，然後更新它

這裏我的代碼不能正常工作。

CREATE TRIGGER tg_new_sms_sent 
AFTER INSERT ON sms 
FOR EACH ROW 
    SET @k = (SELECT id FROM consumption WHERE period = NEW.simple_date); 
    CASE 
     WHEN ISNULL(@k) THEN 
      INSERT INTO consumption (system_id, period, credit, sms) 
      VALUES (NEW.system_id, NEW.simple_date, NEW.used_credit, NEW.sms_count); 
     ELSE 
      UPDATE consumption SET credit = credit + New.used_credit, sms = sms + NEW.sms_count WHERE (system_id = NEW.system_id) AND (period = NEW.simple_date); 
    END CASE 

我該怎麼辦？

Answer 1

試試下面的代碼。

DELIMITER $$ 
CREATE TRIGGER tg_new_sms_sent 
AFTER INSERT ON sms 
FOR EACH ROW 
    BEGIN 
    DECLARE num_rows INT; 

    SELECT COUNT(id) INTO num_rows FROM consumption 
    WHERE system_id = NEW.system_id AND period = NEW.simple_date; 

    IF num_rows = 0 THEN 
     INSERT INTO consumption (system_id, period, credit, sms) 
     VALUES (NEW.system_id, NEW.simple_date, NEW.used_credit, NEW.sms_count); 
    ELSE 
     UPDATE consumption 
     SET credit = credit + NEW.used_credit, sms = sms + NEW.sms_count 
     WHERE system_id = NEW.system_id AND period = NEW.simple_date; 
    END IF; 

    END$$ 
DELIMITER ; 

Answer 2

DELIMITER $$ 
CREATE TRIGGER tg_new_sms_sent AFTER INSERT ON sms 
FOR EACH ROW 
BEGIN 
DECLARE VAR_CNT INT; 
     SELECT id INTO VAR_CNT FROM consumption WHERE period = NEW.simple_date AND system_id = NEW.system_id; 

     IF VAR_CNT = 0 THEN 
     INSERT INTO consumption (system_id, period, credit, sms) 
     VALUES (NEW.system_id, NEW.simple_date, NEW.used_credit, NEW.sms_count); 
     ELSE 
     UPDATE consumption SET credit = credit + New.used_credit, sms = sms + NEW.sms_count WHERE (system_id = NEW.system_id) AND (period = NEW.simple_date); 
     END IF ; 

END;$$ 

DELIMITER ; 

試試上面的查詢。

希望這會幫助你