Convert date of format dd mon yyyy to return integer of month in SQL

Question

I have a varchar variable containing value 01 May 2013 and I need to obtain the integer of the Month part.

for eg if 01 May 2013 is input I should get the result as 5

The query I wrote was :

select DATEPART(MM,CONVERT(DATETIME,CONVERT(VARCHAR(15),'01 '+SUBSTRING(FISCAL_MONTH,1,3)+' 2013'),100))
FROM <table name>

Here FISCAL_MONTH is my column name from the table. However this query is showing me the result, for eg 11 for November but is also throwing the following error : Msg 241, Level 16, State 1, Line 1 Conversion failed when converting date and/or time from character string.

I have tried various combinations, bit in vain. Kindly note I need it in a query. Kindly help.

Answer 1

如果那是您要转换的唯一日期，则可以将SQL语句简化为：

select datepart(mm,convert(datetime,'01 May 2013'))

Answer 2

I just used this to test and it worked:

declare @t as varchar(333)
set @t = '01 May 2013'

select datepart(mm,convert(datetime, @t))

Gives me

5

If you are still getting that conversion error, then you either have some NULL values OR some date values that are not in the correct format . Check the data in your table to see which it is.

Answer 3

I'll leave it to you to add the rest of the months.

select case substring('01 MAY 2013',4,3) when 'JAN' then 1 
when 'FEB' then 2
when 'MAR' then 3    
when 'APR' then 4
when 'MAY' then 5 
when 'JUN' then 6 else 9999 end

Answer 4

It might just be that there is a 3 instead of a 2 in the substring argument:

SUBSTRING(FISCAL_MONTH,1, 2 )+' 2013'),100))

The concat might work also: select DATEPART(MM, CONCAT('01/', substring(convert(varchar(15),'03/23/2013'),1,2),'/2013'));

Answer 5

Wow, it is real interesting to see all the weird code that people come up with. I use the KISS policy most of the time (keep it simple stupid).

How about the MONTH() function. It has been in the TSQL language forever. I even threw in a coalesce to handle any unexpected NULLS.

-- Simple date as text
declare @var_test varchar(20) = '01 may 2013';

-- Use coalesce to handle nulls, use month to return int
select month(coalesce(@var_test, '01 jan 1900')) as my_month_index

Answer 6

Select month ( cast ( date_col as datetime )) From table

Answer 7

You have to convert with proper format, you have to pass the apprpriate format-style value on your conversion. As per MSDN, you are using "dd mon yy" format, so you have to supply the corresponding format-style-code 6 or 106

Declare @FISCAL_MONTH nvarchar(max) = '01 May 2013'
select datepart(mm,Convert(datetime, @FISCAL_MONTH, 6))
--5

Set @FISCAL_MONTH = '01 November 2013'
select datepart(mm,Convert(datetime, @FISCAL_MONTH, 6))
--11