Query comparing dates in SQL

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野趣味
野趣味 2020-11-28 10:18

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 Tes         


        
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  • 2020-11-28 10:39

    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.

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  • 2020-11-28 10:40

    Try like this

    select id,numbers_from,created_date,amount_numbers,SMS_text 
    from Test_Table
    where 
    created_date <= '2013-12-04'
    
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  • 2020-11-28 10:42

    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#
    
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  • 2020-11-28 10:53

    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

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  • 2020-11-28 11:01

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

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  • 2020-11-28 11:04

    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.

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