Dynamic IN with SQL - sql

Question

I have two stored procedure which currently selects from Users (U) where U has a booking which matches some criteria (IsPaid = 1 and MonthNo matches that passed to the stored procedure).
--Users (U)--
UserID Name
1 John
2 Bill
3 Tom
--Bookings (B)--
BookingID UserID MonthNo IsPaid
5 1 2 1
6 1 3 1
7 1 4 0
8 2 2 1
9 2 3 1
10 2 4 1
11 3 4 1
ALTER PROCEDURE FindUsers...
#MonthNo
AS
...
WHERE B.IsPaid = 1 AND B.MonthNo = #MonthNo
So currently, if #MonthId = 3, users #2 and #3 are returned
I now need to pass a list to the procedure to return users where a range of booking match. Ie:
ALTER PROCEDURE FindUsers...
#MonthNosCsv
AS
...
-- split month numbers somehow, then check whether all matching `Booking` rows match.
Pseudo code....
WHERE ALL(B.IsPaid = 1 AND B.MonthNo IN(CsvSplit(#MonthNoCsv)))
So if #MonthNoCsv is '2,3,4', only user 2 is returned, because they have paid bookings in months 2,3 and 4.
Is this possible in SQL or would it be best to do secondary processing in the consuming application?

Answer 1

Everyone should have a good splitter. There are many options available. I did, however, supply the one I used.
The following list two options, the first is an in-line version, and the second uses a parse function. Both would return the same results.
Option 1 - Without a Parse Function
Declare #MonthNoCsv varchar(50) = '2,3,4'
;with cte as (
Select RetSeq = Row_Number() over (Order By (Select null))
,RetVal = LTrim(RTrim(B.i.value('(./text())[1]', 'varchar(max)')))
From (Select x = Cast('<x>' + replace((Select replace(#MonthNoCsv,',','§§Split§§') as [*] For XML Path('')),'§§Split§§','</x><x>')+'</x>' as xml).query('.')) as A
Cross Apply x.nodes('x') AS B(i)
)
Select U.*
from cte M
Join Bookings B on M.RetVal=B.MonthNo and B.IsPaid=1
Join Users U on U.UserID=B.UserID
Group By U.UserID,U.Name
Having Count(Distinct B.MonthNo)=(Select max(RetSeq) from cte)
Option 2 - With a Parse Function
Declare #MonthNoCsv varchar(50) = '2,3,4'
;with cte as (
Select * from [dbo].[udf-Str-Parse](#MonthNoCsv,',')
)
Select U.*
from cte M
Join Bookings B on M.RetVal=B.MonthNo and B.IsPaid=1
Join Users U on U.UserID=B.UserID
Group By U.UserID,U.Name
Having Count(Distinct B.MonthNo)=(Select max(RetSeq) from cte)
Both Return
UserID Name
2 Bill
The UDF if Interested
CREATE FUNCTION [dbo].[udf-Str-Parse] (#String varchar(max),#Delimiter varchar(10))
Returns Table
As
Return (
Select RetSeq = Row_Number() over (Order By (Select null))
,RetVal = LTrim(RTrim(B.i.value('(./text())[1]', 'varchar(max)')))
From (Select x = Cast('<x>' + replace((Select replace(#String,#Delimiter,'§§Split§§') as [*] For XML Path('')),'§§Split§§','</x><x>')+'</x>' as xml).query('.')) as A
Cross Apply x.nodes('x') AS B(i)
);
--Thanks Shnugo for making this XML safe
--Select * from [dbo].[udf-Str-Parse]('Dog,Cat,House,Car',',')
--Select * from [dbo].[udf-Str-Parse]('John Cappelletti was here',' ')
--Select * from [dbo].[udf-Str-Parse]('this,is,<test>,for,< & >',',')