Set Static Day and Previous Month GETDATE() SQL

Question

The following SQL statement sets the date for a particular column:

DATEDUE=convert(varchar,GETDATE(),103 )

However, its sets the current date such as 05/08/2015. What I wish to do is to have it in the same dd/mm/yyyy format but to set the day to the 15th and the month to the previous month, so 05/08/2015 should be 15/07/2015 instead.

Answer 1

select CONVERT(VARCHAR(10),
              DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE())-1, 0) + 14
              ,103)

 Result: 15/07/2015

Important Note

Since DATEDUE column is storing dates, you should really use the sql server DATE data type for storing date values in that column.

Answer 2

if you decide you just need the most recent previous 15th of the month you can use this.

SELECT CONVERT(VARCHAR(10),
       DATEADD(DAY,14,DATEADD(MONTH,DATEDIFF(MONTH,0,GETDATE()) - 
       (CASE WHEN DATEPART(DAY,GETDATE()) > 15 THEN 0 ELSE 1 END), 0)),
       103)

05/08/2015 becomes 15/07/2015 and 24/08/2015 becomes 15/08/2015 instead of 15/07/2015