T-SQL - 将日期时间更改为日期数据类型?

问题描述

我在使用 datetime 数据类型的表中有一个 BirthDate 列.目前，这些值类似于格式 1987-12-30 00:00:00.000.

I have a column BirthDate in a table that is using the datetime data type. Currently, the values resemble the format 1987-12-30 00:00:00.000.

我想更新此表的所有行，将它们更改为具有 date 数据类型的以下格式:1987-12-30

I would like to update all the rows of this table, changing them to the following format with the date data type: 1987-12-30

我可以运行 SELECT...

I can run a SELECT...

SELECT CONVERT(date, BirthDate) FROM CUSTOMERLIST

但这只会影响显示.我希望它更新整个列并更改该属性的数据类型.任何帮助将不胜感激！

But this is only affecting the display. I would like for it to update the entire column and also change the data type of that attribute as well. Any assistance would be greatly appreciated!

推荐答案

您需要ALTER 表格:

You will need to ALTER the table:

ALTER TABLE CUSTOMERLIST ALTER COLUMN BirthDate date not null

参见 Sql Fiddle 和演示