Select time value or date value from datetime with C# odbc

问题

I have a SQL query being sent by C# system.data.odbc OdbcCommand object.

SELECT Calldate 
  FROM calls;

The Calldate column is a datetime type.

I want the select statement to only return the date portion of the value. The DateValue function doesn't seem to do anything. I am hoping to achieve this within the SQL provided to the OdbcCommand object.

Edit 1: The resource being queried is an access mdb file.

回答1:

Given you are using sql server, you can convert the datetime

select convert(datetime, CallDate, x) from calls

x can represent different notations/numeric values for different date formatting. See this link for all the different numeric values, and the examples of their output.

http://linesofcode.net/snippets/45

EDIT (based on the fact that OP is using access, not SQL server)

You can format any string using the MS format function:

SELECT Format(CallDate,'yyyy/mm/dd') FROM calls

more formatting options here: http://www.webcheatsheet.com/SQL/access_functions/format.php

回答2:

How about -

select datevalue(Calldate) from calls;

Other functions listed here

来源：https://stackoverflow.com/questions/5865066/select-time-value-or-date-value-from-datetime-with-c-sharp-odbc