Fetch month name based on various dates in table - sql

Question

I have one table that contains BillDate column i.e. Bill Dates for various customers. The bill date range from September 1 to September 30. Based on the billdate, I want to fetch Month name in format "Sep-19" (19 being year 2019)
The issue is that from next month, the BillDate will have records for both September and October 2019.
For Oct 2019, the bill month that I want to fetch is "Oct-19" as I will create a report based on data present for bills in October month.
How to fetch bill month based on data that changes every month?

Answer 1

One method uses format():
select format(BillDate, 'MMM-yy')
A more old-fashioned method constructs the string:
select left(datename(month, BillDate), 3) + '-' + right(datename(year), BillDate), 2)

Answer 2

FORMAT is an awful function for this, it's horrifically slow. I highly recommend CONVERT and a style code, along with some string manipulation.
REPLACE(STUFF(CONVERT(varchar(11),BillDate,106),1,3,''),' ','-')

Answer 3

You can try this:
SELECT REPLACE(RIGHT(CONVERT(VARCHAR(20), BillDate, 106), 8), ' ', '-')
For Getting Most Recent Data you can try this
SELECT REPLACE(RIGHT(CONVERT(VARCHAR(20), BillDate, 106), 8), ' ', '-') AS 'YourColumnName' FROM TableName
ORDER BY BillDate DESC
For Testing Purpose:-
SELECT REPLACE(RIGHT(CONVERT(VARCHAR(20), GETDATE(), 106), 8), ' ', '-') AS 'CurrentDate'
Output:-
CurrentDate
-----------
Oct-2019

Answer 4

Use the format function to convert the date in your format. And then you can use the where function to get the results for current month (oct 2019).
Note: Format is small and nice function if you're using to build this report query for small data. But if you're working with relatively large datasets I would recommend convert as format would have affect on performance.
Select *
From
(select your_field1, your_field2, format(BillDate, 'MMM-yy') as Current_Date from your_table) as alias_table
Where [Current_Date] = format(GETDATE(), 'MMM-yy');
In SQL you cannot use alias columns names within the same query that is why I have used a subquery in paranthesis to force SQL to handle where before select.