MYSQL TRIGGER子查詢更新

Question

我是使用SQL的新手，我在SQLSERVER中開發了一個運行完美的觸發器，現在我正嘗試將其轉換為可在Mysql中使用，但不起作用，我也不知道該怎么做。

這是代碼：

CREATE TRIGGER tg_test AFTER UPDATE ON  YET FOR EACH ROW

INSERT INTO CONTROLETRIGGER(idAluno, idNivel)
values(NEW.IdAluno, NEW.idNivel);


UPDATE HistoricoNivel AS E
join(
select max(h.idNivel) Nivel, h.idAluno
from HistoricoNivel h
join CONTROLETRIGGER v on h.idaluno = v.idaluno
WHERE h.dtFim is null
group by h.idAluno
)X on E.idAluno = X.idAluno and E.idNivel= X.Nivel
join CONTROLETRIGGER vi on vi.idaluno = E.idAluno
set E.dtFim = case when X.idnivel <> vi.idNivel then CURRENT_DATE() else null end

拜托，我做錯了什么？

Tks。

Answer 1

X子查詢沒有名為idnivel的字段，因此case語句將不會編譯。

我假設您想要的是nivel ，它將觸發全部觸發；

CREATE TRIGGER tg_test AFTER UPDATE ON  YET FOR EACH ROW
 INSERT INTO CONTROLETRIGGER(idAluno, idNivel) VALUES (NEW.IdAluno, NEW.idNivel);
 UPDATE HistoricoNivel AS E
 JOIN(
  SELECT MAX(h.idNivel) Nivel, h.idAluno
  FROM HistoricoNivel h
  JOIN CONTROLETRIGGER v ON h.idaluno = v.idaluno
  WHERE h.dtFim IS NULL
  GROUP BY h.idAluno
 ) X 
 ON E.idAluno = X.idAluno AND E.idNivel= X.Nivel
 JOIN CONTROLETRIGGER vi ON vi.idaluno = E.idAluno
 SET E.dtFim = CASE WHEN X.nivel <> vi.idNivel THEN CURRENT_DATE() ELSE NULL END
//

看到它在這里編譯 。