How to convert int to date in SQL Server 2008

2020-02-05 03:46发布

问题:

I am using MS SQL Server 2008, and in a table I have column idate as date but in the integer format. But in the query I want that in the date format. Is it possible to convert integer date into proper datetime format?

回答1:

You can't convert an integer value straight to a date but you can first it to a datetime then to a date type

select cast(40835 as datetime)

and then convert to a date (SQL 2008)

select cast(cast(40835 as datetime) as date)

cheers



回答2:

You have to first convert it into datetime, then to date.

Try this, it might be helpful:

Select Convert(DATETIME, LEFT(20130101, 8))

then convert to date.



回答3:

You most likely want to examine the documentation for T-SQL's CAST and CONVERT functions, located in the documentation here: http://msdn.microsoft.com/en-US/library/ms187928(v=SQL.90).aspx

You will then use one of those functions in your T-SQL query to convert the [idate] column from the database into the datetime format of your liking in the output.



回答4:

Reading through this helps solve a similar problem. The data is in decimal datatype - [DOB] [decimal](8, 0) NOT NULL - eg - 19700109. I want to get at the month. The solution is to combine SUBSTRING with CONVERT to VARCHAR.

    SELECT [NUM]
       ,SUBSTRING(CONVERT(VARCHAR, DOB),5,2) AS mob
    FROM [Dbname].[dbo].[Tablename] 


回答5:

If your integer is timestamp in milliseconds use:

SELECT strftime("%Y-%d-%m", col_name, 'unixepoch') AS col_name

It will format milliseconds to yyyy-mm-dd string.