How do you update a DateTime field in T-SQL?

Question

The following query does not update the datetime field:

update table
SET EndDate = \'2009-05-25\'
WHERE Id = 1

I also tried it with no dashes,

Answer 1

Using a DateTime parameter is the best way. However, if you still want to pass a DateTime as a string, then the CAST should not be necessary provided that a language agnostic format is used.

e.g.

Given a table created like :

create table t1 (id int, EndDate DATETIME)
insert t1 (id, EndDate) values (1, GETDATE())

The following should always work :

update t1 set EndDate = '20100525' where id = 1 -- YYYYMMDD is language agnostic

The following will work :

SET LANGUAGE us_english
update t1 set EndDate = '2010-05-25' where id = 1

However, this won't :

SET LANGUAGE british
update t1 set EndDate = '2010-05-25' where id = 1  

This is because 'YYYY-MM-DD' is not a language agnostic format (from SQL server's point of view) .

The ISO 'YYYY-MM-DDThh:mm:ss' format is also language agnostic, and useful when you need to pass a non-zero time.

More info : http://karaszi.com/the-ultimate-guide-to-the-datetime-datatypes