Question

我想知道如何检查（StartTime列）中的时间戳是否大于系统时间。如果更大，则应将时间戳重置为NULL

有办法吗？

问候。

Answer 1

update table set ts_field = null where ts_field > now()

这是针对mysql的

Answer 2

在MySQL中你可以尝试：

UPDATE table SET time = NULL
WHERE time>NOW()

如果您想要它是自动的，请尝试：

CREATE TRIGGER upd BEFORE INSERT ON `table` 
FOR EACH ROW BEGIN 
    IF NEW.time>NOW() THEN SET NEW.time=NULL; END IF; 
END;

Answer 3

Declare @Now datetime = GETDATE()

Update tbl Set
    StartTime=NULL
Where StartTime > @Now

Answer 4

  create trigger tbl_reset_date
  on tbl
  after insert
  as

  update t
  set time = null
  from tbl t
   join inserted i
     on i.id = t.id
  where i.time > getdate();

Answer 5

...试

CREATE TRIGGER tr_Product_InsteadOfTrigger 
ON Product
INSTEAD OF INSERT
AS

  IF @@ROWCOUNT > 0 -- limit nested recursion if no work to do
  BEGIN

    SET NOCOUNT ON;

    INSERT INTO Product
    (
      ProductId,
      PTime 
    )
    SELECT 
      i.ProductId, 
      CASE 
        WHEN i.PTime > GETUTCDATE() 
        THEN NULL 
        ELSE i.PTime 
      END
    FROM 
      inserted i

  END -- if work to do

GO

SQL：检查时间列是否大于系统时间

5 个答案: