Get all records by month in SQL - sql

Question

I am trying to pull records from a view that shows records for the next 90 days. I need a way to pull those records out by month only. I need that because not all months contain 30 days. Here is an example that shows records from today, and for the next 30 days.
select *
from [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
where PRD.ExpDate BETWEEN GETDATE() AND DATEADD(DD, 30, GETDATE())
order by PRD.ExpDate
This gets all records from today and the next 30 days but, I want a way to capture ALL records for the month. Since it's November, the previous 5 days and the rest of the month.

Answer 1

Here is a query for the current month:
SELECT *
FROM [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
WHERE
PRD.ExpDate >= DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0) AND
PRD.ExpDate < DATEADD(mm, 1, DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0));
For the second month, use this WHERE clause:
WHERE
PRD.ExpDate >= DATEADD(mm, 1, DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0)) AND
PRD.ExpDate < DATEADD(mm, 2, DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0));
And continue this way for the third and subsequent months. If you want just a single query for the current and next two months, then use this:
SELECT *
FROM [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
WHERE
PRD.ExpDate >= DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0) AND
PRD.ExpDate < DATEADD(mm, 3, DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0))
ORDER BY
PRD.ExpDate;
You should see each of the three months, in separate blocks, from earliest record to latest record.

Answer 2

Throwing this out as an answer, rather than a comment - this should return all rows for a given month, based on each day of "this month"
SELECT *
FROM [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
WHERE
DATEPART(MONTH,PRD.ExpDate) = DATEPART(MONTH,GetDate())
AND DATEPART(YEAR, PRD.ExpDate) = DATEPART(YEAR, GETDATE())
Add:
You may need an index on your ExpDate field, as per How to improve performance for datetime filtering in SQL Server?

Answer 3

#Tim Biegeleisen I found a few things with your answer. I tried using the SQL month() function but, due to earlier conversion in the DB it would never execute. That answers why #JonTout answer would not work correctly. I was able to accomplish what I wanted to by doing it this way.
DECLARE #mydate DATE, #myEndDate DATE;
SET #mydate = '12/01/2018';
SET #myEndDate = '12/31/2018';
SELECT *
FROM [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
WHERE PRD.ExpDate >= DATEADD(mm, DATEDIFF(mm, 0, #mydate), 0) AND
PRD.ExpDate < DATEADD(mm, 1, DATEADD(mm, DATEDIFF(mm, 0, #myEndDate), 0))
order by ExpDate
I am grateful for your help #Tim Biegeleisen. I found another solution to the problem I was having. This will display all records in the current month and allow me make a stored procedure for a user to choose what month they want for the next 90 days.
DECLARE #Diff Int
Set #Diff = 0
SELECT PRD.Client, PRD.ExpDate
FROM [dbo].[vPolicy_Renewal_90DayLookUp] AS PRD
where (Year(ExpDate) = YEAR(getdate()))
AND DATENAME(month, ExpDate) = DATENAME(MONTH, (Dateadd(Month, #Diff,GETDATE())))
order by ExpDate asc
I could do the same without the year() but, it works for now. I found this way to make a bit more sense to me.