Multiple value IF statement, to show in select - sql-server

Question

Any help appreciated,
the code below is from a database which someone made, every time a receipt is made a unique receipt id is issued. same when a reversal is made a new receipt is issued. what links the two are the pay in number. If a reverse is issued, the reverse flag changes on the old receipt to Y and the new one says N. i have my query that select Minimum date and Max data, for receipts returned will have a much later date that when it was first created. The issue is when there is no reverse, it still pulls information as the min and max date are the same. I am fully aware that i need an if statement, but have no idea how to do it since i am new to Databases.
Select distinct r.receipt_date, r.receipt_no, r.doc_no as Payin_No,r.trans_amt,l.location_desc, ct.charge_type_desc,
(select un.first_name + ' ' + un.last_name)as cashier,
r.payee, r.comments, r.reverse_flag, ret1.returned_by, ret1.return_date
from Cashier..receipts as r
inner join Cashier..location as l on r.location_id=l.location_id
inner join [Cashier].[dbo].[charge_type] as ct on ct.charge_type_no=r.charge_type_no
inner join Cashier..user_name as un on un.user_name=(UPPER(r.created_by))
inner join (
select receipt_no as Return_Receipt ,
(select un2.first_name + ' ' + un2.last_name) as returned_by,
created_date as return_date, doc_no as Payin_no,
r1.reverse_flag
from Cashier..receipts as r1
inner join Cashier..user_name as un2 on un2.user_name=(UPPER(r1.created_by))
where doc_no = r1.doc_no
and created_date = (select MAX(created_date)
from Cashier..receipts where doc_no = r1.doc_no)) as ret1
on (ret1.Payin_no=r.doc_no)
where r.receipt_date = (select MIN(r1.receipt_date) from Cashier..receipts as r1 where r1.receipt_no = r.receipt_no )
Issue i am having, the return by is the same as created
Desired result

Answer 1

Is this basically what you're trying to do?
-- test data creation, for me
create table receipts (receipt_no int, receipt_date datetime, doc_no int, reverse_flag char(1), returned_by varchar(10), create_date datetime, created_date datetime)
insert into receipts values (1, '1/1/2016', 12345, 'Y', 'John', null, '1/1/2016')
insert into receipts values (2, '2/15/2016', 12345, 'N', null, '2/15/2016', '2/15/2016')
SELECT r.receipt_date, r.receipt_no, r.doc_no, r.reverse_flag, ret1.return_date
FROM receipts r
INNER JOIN (
SELECT doc_no, create_date as return_date
FROM receipts
WHERE reverse_flag = 'N')ret1 on r.doc_no = ret1.doc_no and ret1.return_date > r.receipt_date
WHERE r.reverse_flag = 'Y' and r.doc_no = 12345
If that's your goal, I think you just tack this on to the very end of your query:
and r.receipt_date < ret1.return_date
Edit: Based on your update, I think tack this onto the end:
and convert(date, r.receipt_date) < convert(date, ret1.return_date)

Answer 2

I'm still really not sure what you want.
select *
from ( select doc_no, min(receipt_date) as min_receipt_date
from receipts group by doc_no ) as min_receipt
left outer join ( select doc_no, max(receipt_date) as max_receipt_date
from receipts group by doc_no) as max_receipt
on min_receipt.doc_no = max_receipt.doc_no and
min_receipt.min_receipt_date <> max_receipt.max_receipt_date
for
insert into receipts values (1, '2016-01-01', 12345, 'Y', 'John', null, '2016-01-01');
insert into receipts values (2, '2016-03-15', 12345, 'N', null, '2016-03-15', '2016-03-15');
insert into receipts values (3, '2016-03-15', 123667, 'N', null, '2016-03-15', '2016-03-15');
yields
doc_no min_receipt_date doc_no max_receipt_date
12345 January, 01 2016 00:00:00 12345 March, 15 2016 00:00:00
123667 March, 15 2016 00:00:00 (null) (null)
but it assumes that the return date will never be the same as the original receipt date. I also left off the Y and N flags because I don't see how it's necessary if the min date is always the original purchase date. The other answer here uses the created_date but in your screenshot of the table data, you only show one date so I wrote it assuming only one date (the receipt date). I tested that on MySQL because SQLFiddle was hating on my SQL Server syntax for inserts and I don't have another way to test right now.

Answer 3

This is what i was looking for, figured it out. Thank you Max for opening insights on how i could tackle the problem.
Select distinct r.receipt_date, r.receipt_no, r.doc_no as Payin_No,r.trans_amt,l.location_desc, ct.charge_type_desc,
(select un.first_name + ' ' + un.last_name)as cashier,
r.payee, r.comments, r.cost_centre, r.item, r.programme, r.activity, r.btl_sof, r.reverse_flag, --, ret1.returned_by, ret1.return_date
(case when r.reverse_flag = 'Y' then (select (un2.first_name + ' ' + un2.last_name)from Cashier..receipts as r1
inner join Cashier..user_name as un2 on un2.user_name=(UPPER(r1.created_by)) where created_date = (select MAX(created_date)
from Cashier..receipts where doc_no = r.doc_no)) end ) as returned_by ,
(case when r.reverse_flag = 'Y' then (select created_date from Cashier..receipts as r1
inner join Cashier..user_name as un2 on un2.user_name=(UPPER(r1.created_by)) where created_date = (select MAX(created_date)
from Cashier..receipts where doc_no = r.doc_no)) end ) as returned_date
from Cashier..receipts as r
inner join Cashier..location as l on r.location_id=l.location_id
inner join [Cashier].[dbo].[charge_type] as ct on ct.charge_type_no=r.charge_type_no
inner join Cashier..user_name as un on un.user_name=(UPPER(r.created_by))
where r.receipt_date = (select MIN(r1.receipt_date) from Cashier..receipts as r1 where r1.receipt_no = r.receipt_no )