94
votes

I have a table with dates that all happened in the month November. I wrote this query

select id,numbers_from,created_date,amount_numbers,SMS_text 
from Test_Table
where 
created_date <= '2013-04-12'

This query should return everything that happened in month 11 (November) because it happened before the date '2013-04-12' (in December)

But it's only returning available dates that happened in days lesser than 04 (2013-04-12)

Could it be that it's only comparing the day part? and not the whole date?

How to fix this?

Created_date is of type date

Date format is by default yyyy-dd-MM

9
You are comparing dates to strings, not dates to dates - Panagiotis Kanavos
Maybe it thinks 2013-04-12? is April 12th? Or maybe created_dateis a string and not a date? - jpw
Look at Cast & Convert on T-SQL manual and use the appropriate conversion for your locale - Steve
No need to cast at all, just use the invariant format '20130412' - Panagiotis Kanavos
Instead of sending a string with the date then, try creating a parameterized query and pass the date as a date-typed parameter. BTW what version of SQL Server are you using? DATE was added in SQL Server 2008. - Panagiotis Kanavos

9 Answers

95
votes

Instead of '2013-04-12' whose meaning depends on the local culture, use '20130412' which is recognized as the culture invariant format.

If you want to compare with December 4th, you should write '20131204'. If you want to compare with April 12th, you should write '20130412'.

The article Write International Transact-SQL Statements from SQL Server's documentation explains how to write statements that are culture invariant:

Applications that use other APIs, or Transact-SQL scripts, stored procedures, and triggers, should use the unseparated numeric strings. For example, yyyymmdd as 19980924.

EDIT

Since you are using ADO, the best option is to parameterize the query and pass the date value as a date parameter. This way you avoid the format issue entirely and gain the performance benefits of parameterized queries as well.

UPDATE

To use the the the ISO 8601 format in a literal, all elements must be specified. To quote from the ISO 8601 section of datetime's documentation

To use the ISO 8601 format, you must specify each element in the format. This also includes the T, the colons (:), and the period (.) that are shown in the format.

... the fraction of second component is optional. The time component is specified in the 24-hour format.

35
votes

Try like this

select id,numbers_from,created_date,amount_numbers,SMS_text 
from Test_Table
where 
created_date <= '2013-12-04'
13
votes

If You are comparing only with the date vale, then converting it to date (not datetime) will work

select id,numbers_from,created_date,amount_numbers,SMS_text 
 from Test_Table
 where 
 created_date <= convert(date,'2013-04-12',102)

This conversion is also applicable during using GetDate() function

4
votes

please try with below query

select id,numbers_from,created_date,amount_numbers,SMS_text 
from Test_Table
where 
convert(datetime, convert(varchar(10), created_date, 102))  <= convert(datetime,'2013-04-12')
4
votes

You put <= and it will catch the given date too. You can replace it with < only.

0
votes

Date format is yyyy-mm-dd. So the above query is looking for records older than 12Apr2013

Suggest you do a quick check by setting the date string to '2013-04-30', if no sql error, date format is confirmed to yyyy-mm-dd.

0
votes

Try to use "#" before and after of the date and be sure of your system date format. maybe "YYYYMMDD O YYYY-MM-DD O MM-DD-YYYY O USING '/ O \' "

Ex:

 select id,numbers_from,created_date,amount_numbers,SMS_text 
 from Test_Table
 where 
 created_date <= #2013-04-12#
0
votes

Convert them to dates in the same format and then you can compare. Τry like this:

where convert(date, created_date,102) <= convert(date,                                  /*102 is ANSI format*/
                                                    substring('2013-04-12',1,4) + '.' + /*year*/
                                                    substring('2013-04-12',9,2) + '.' + /*month*/
                                                    substring('2013-04-12',6,2)         /*day*/
                                                ,102)
0
votes

you can also use to_char(column_name, 'YYYY-MM-DD) to change format