I need to find the last P.O.for parts purchased from Vendors.
I was trying to come up with a way to do this using a query I found that allowed me to find
the max Creation date for a group of Quotes linked to an Opportunity:
SELECT
t1.[quoteid]
,t1.[OpportunityId]
,t1.[Name]
FROM
[Quote] t1
WHERE
t1.[CreatedOn] = (SELECT MAX(t2.[CreatedOn])
FROM [Quote] t2
WHERE t2.[OpportunityId] = t1.[OpportunityId])
In the case of Purchase Orders, though, I have a header table and a line item table.
So, I need to include info from both:
SELECT
PURCHASE_ORDER.ORDER_DATE
,PURC_ORDER_LINE.PURC_ORDER_ID
,PURC_ORDER_LINE.PART_ID
,PURC_ORDER_LINE.UNIT_PRICE
,PURC_ORDER_LINE.USER_ORDER_QTY
FROM
PURCHASE_ORDER,
PURC_ORDER_LINE
WHERE
PURCHASE_ORDER.ID=
PURC_ORDER_LINE.PURC_ORDER_ID
If the ORDER_DATE from the header were available in the PURC_ORDER_LINE table I thought
this could be done like so:
SELECT
PURC_ORDER_LINE.ORDER_DATE
,PURC_ORDER_LINE.PURC_ORDER_ID
,PURC_ORDER_LINE.PART_ID
,PURC_ORDER_LINE.UNIT_PRICE
,PURC_ORDER_LINE.USER_ORDER_QTY
FROM
PURC_ORDER_LINE T1
WHERE T1.ORDER_DATE=(SELECT MAX(T2.ORDER_DATE)
FROM PURC_ORDER_LINE T2
WHERE T2.PURC_ORDER_ID=T1.PURC_ORDER_ID)
But I'm not sure that's correct and, in any case, there are 2 things:
The ORDER_DATE is in the Header table, not in the line table
I need the last P.O. created for each of the Parts (PART_ID)
So:
PART_A and PART_B, as an example, may appear on several P.O.s
Part
Order Date
P.O. #
PART_A
2020-08-17
PO12345
PART_A
2020-11-21
PO23456
PART_A
2021-07-08
PO29986
PART_B
2019-11-30
PO00861
PART_B
2021-08-30
PO30001
The result set would be (including the other fields from above):
ORDER_DATE
PURC_ORDER_ID
PART_ID
UNIT_PRICE
ORDER_QTY
2021-07-08
PO29986
PART_A
321.00
12
2021-08-30
PO30001
PART_B
426.30
8
I need a query that will give me such a result set.
You can use row-numbering for this. Just place the whole join inside a subquery (derived table), add a row-number, then filter on the outside.
SELECT *
FROM (
SELECT
pol.PART_ID,
po.ORDER_DATE,
pol.PURC_ORDER_ID,
pol.UNIT_PRICE,
pol.USER_ORDER_QTY,
rn = ROW_NUMBER() OVER (PARTITION BY pol.PART_ID ORDER BY po.ORDER_DATE DESC)
FROM PURCHASE_ORDER po
JOIN PURC_ORDER_LINE pol ON po.ID = pol.PURC_ORDER_ID
) po
WHERE po.rn = 1;
Note the use of proper join syntax, as well as table aliases
you can use window function:
select * from (
select * , row_number() over (partition by PART_ID order by ORDER_DATE desc) rn
from tablename
) t where t.rn = 1
Related
I wrote a query which uses 2 temp tables. And then joins them into 1. However, I am seeing duplicate records in the student visit temp table. (Query is below). How could this be modified to remove the duplicate records of the visit temp table?
with clientbridge as (Select *
from (Select visitorid, --Visid
roomnumber,
room_id,
profid,
student_id,
ambc.datekey,
RANK() over(PARTITION BY visitorid,student_id,profid ORDER BY ambc.datekey desc) as rn
from university.course_office_hour_bridge cohd
--where student_id = '9999999-aaaa-6634-bbbb-96fa18a9046e'
)
where rn = 1 --visitorid = '999999999999999999999999999999'---'1111111111111111111111111111111' --and pai.datekey is not null --- 00000000000000000000000000
),
-----------------Data Header Table
studentvisit as
(SELECT
--Visit key will allow us to track everything they did within that visit.
distinct visid_visitorid,
--calcualted_visitorid,
uniquevisitkey,
--channel, -- says the room they're in. Channel might not be reliable would need to see how that operates
--office_list, -- add 7 to exact
--user_college,
--first_office_hour_name,
--first_question_time_attended,
studentaccountid_5,
profid_officenumber_8,
studentvisitstarttime,
room_id_115,
--date_time,
qqq144, --Course Name
qqq145, -- Course Office Hour Benefit
qqq146, --Course Office Hour ID
datekey
FROM university.office_hour_details ohd
--left_join niversity.course_office_hour_bridge cohd on ohd.visid_visitorid
where DateKey >='2022-10-01' --between '2022-10-01' and '2022-10-27'
and (qqq146 <> '')
)
select
*
from clientbridge ab inner join studentvisit sv on sv.visid_visitorid = cb.visitorid
I wrote a query which uses 2 temp tables. And then joins them into 1. However, I am seeing duplicate records in the student visit temp table. (Query is below). How could this be modified to remove the duplicate records of the visit temp table?
I think you may get have a better shot by joining the two datasets in the same query where you want the data ranked, otherwise your rank from query will be ignored within the results from the second query. Perhaps, something like ->
;with studentvisit as
(SELECT
--Visit key will allow us to track everything they did within that visit.
distinct visid_visitorid,
--calcualted_visitorid,
uniquevisitkey,
--channel, -- says the room they're in. Channel might not be reliable would need to see how that operates
--office_list, -- add 7 to exact
--user_college,
--first_office_hour_name,
--first_question_time_attended,
studentaccountid_5,
profid_officenumber_8,
studentvisitstarttime,
room_id_115,
--date_time,
qqq144, --Course Name
qqq145, -- Course Office Hour Benefit
qqq146, --Course Office Hour ID
datekey
FROM university.office_hour_details ohd
--left_join niversity.course_office_hour_bridge cohd on ohd.visid_visitorid
where DateKey >='2022-10-01' --between '2022-10-01' and '2022-10-27'
and (qqq146 <> '')
)
,clientbridge as (
Select
sv.*,
university.course_office_hour_bridge cohd, --Visid
roomnumber,
room_id,
profid,
student_id,
ambc.datekey,
RANK() over(PARTITION BY sv.visitorid,sv.student_id,sv,profid ORDER BY ambc.datekey desc) as rn
from university.course_office_hour_bridge cohd
inner join studentvisit sv on sv.visid_visitorid = cohd.visitorid
)
select
*
from clientbridge WHERE rn=1
I need to update the following query so that it only returns one child record (remittance) per parent (claim).
Table Remit_To_Activate contains exactly one date/timestamp per claim, which is what I wanted.
But when I join the full Remittance table to it, since some claims have multiple remittances with the same date/timestamps, the outermost query returns more than 1 row per claim for those claim IDs.
SELECT * FROM REMITTANCE
WHERE BILLED_AMOUNT>0 AND ACTIVE=0
AND REMITTANCE_UUID IN (
SELECT REMITTANCE_UUID FROM Claims_Group2 G2
INNER JOIN Remit_To_Activate t ON (
(t.ClaimID = G2.CLAIM_ID) AND
(t.DATE_OF_LATEST_REGULAR_REMIT = G2.CREATE_DATETIME)
)
where ACTIVE=0 and BILLED_AMOUNT>0
)
I believe the problem would be resolved if I included REMITTANCE_UUID as a column in Remit_To_Activate. That's the REAL issue. This is how I created the Remit_To_Activate table (trying to get the most recent remittance for a claim):
SELECT MAX(create_datetime) as DATE_OF_LATEST_REMIT,
MAX(claim_id) AS ClaimID,
INTO Latest_Remit_To_Activate
FROM Claims_Group2
WHERE BILLED_AMOUNT>0
GROUP BY Claim_ID
ORDER BY Claim_ID
Claims_Group2 contains these fields:
REMITTANCE_UUID,
CLAIM_ID,
BILLED_AMOUNT,
CREATE_DATETIME
Here are the 2 rows that are currently giving me the problem--they're both remitts for the SAME CLAIM, with the SAME TIMESTAMP. I only want one of them in the Remits_To_Activate table, so only ONE remittance will be "activated" per Claim:
enter image description here
You can change your query like this:
SELECT
p.*, latest_remit.DATE_OF_LATEST_REMIT
FROM
Remittance AS p inner join
(SELECT MAX(create_datetime) as DATE_OF_LATEST_REMIT,
claim_id,
FROM Claims_Group2
WHERE BILLED_AMOUNT>0
GROUP BY Claim_ID
ORDER BY Claim_ID) as latest_remit
on latest_remit.claim_id = p.claim_id;
This will give you only one row. Untested (so please run and make changes).
Without having more information on the structure of your database -- especially the structure of Claims_Group2 and REMITTANCE, and the relationship between them, it's not really possible to advise you on how to introduce a remittance UUID into DATE_OF_LATEST_REMIT.
Since you are using SQL Server, however, it is possible to use a window function to introduce a synthetic means to choose among remittances having the same timestamp. For example, it looks like you could approach the problem something like this:
select *
from (
select
r.*,
row_number() over (partition by cg2.claim_id order by cg2.create_datetime desc) as rn
from
remittance r
join claims_group2 cg2
on r.remittance_uuid = cg2.remittance_uuid
where
r.active = 0
and r.billed_amount > 0
and cg2.active = 0
and cg2.billed_amount > 0
) t
where t.rn = 1
Note that that that does not depend on your DATE_OF_LATEST_REMIT table at all, it having been subsumed into the inline view. Note also that this will introduce one extra column into your results, though you could avoid that by enumerating the columns of table remittance in the outer select clause.
It also seems odd to be filtering on two sets of active and billed_amount columns, but that appears to follow from what you were doing in your original queries. In that vein, I urge you to check the results carefully, as lifting the filter conditions on cg2 columns up to the level of the join to remittance yields a result that may return rows that the original query did not (but never more than one per claim_id).
A co-worker offered me this elegant demonstration of a solution. I'd never used "over" or "partition" before. Works great! Thank you John and Gaurasvsa for your input.
if OBJECT_ID('tempdb..#t') is not null
drop table #t
select *, ROW_NUMBER() over (partition by CLAIM_ID order by CLAIM_ID) as ROW_NUM
into #t
from
(
select '2018-08-15 13:07:50.933' as CREATE_DATE, 1 as CLAIM_ID, NEWID() as
REMIT_UUID
union select '2018-08-15 13:07:50.933', 1, NEWID()
union select '2017-12-31 10:00:00.000', 2, NEWID()
) x
select *
from #t
order by CLAIM_ID, ROW_NUM
select CREATE_DATE, MAX(CLAIM_ID), MAX(REMIT_UUID)
from #t
where ROW_NUM = 1
group by CREATE_DATE
If I have following table in Postgres:
order_dtls
Order_id Order_date Customer_name
-------------------------------------
1 11/09/17 Xyz
2 15/09/17 Lmn
3 12/09/17 Xyz
4 18/09/17 Abc
5 15/09/17 Xyz
6 25/09/17 Lmn
7 19/09/17 Abc
I want to retrieve such customer who has placed orders on 2 consecutive days.
In above case Xyz and Abc customers should be returned by query as result.
There are many ways to do this. Use an EXISTS semi-join followed by DISTINCT or GROUP BY, should be among the fastest.
Postgres syntax:
SELECT DISTINCT customer_name
FROM order_dtls o
WHERE EXISTS (
SELEST 1 FROM order_dtls
WHERE customer_name = o.customer_name
AND order_date = o.order_date + 1 -- simple syntax for data type "date" in Postgres!
);
If the table is big, be sure to have an index on (customer_name, order_date) to make it fast - index items in this order.
To clarify, since Oto happened to post almost the same solution a bit faster:
DISTINCT is an SQL construct, a syntax element, not a function. Do not use parentheses like DISTINCT (customer_name). Would be short for DISTINCT ROW(customer_name) - a row constructor unrelated to DISTINCT - and just noise for the simple case with a single expression, because Postgres removes the pointless row wrapper for a single element automatically. But if you wrap more than one expression like that, you get an actual row type - an anonymous record actually, since no row type is given. Most certainly not what you want.
What is a row constructor used for?
Also, don't confuse DISTINCT with DISTINCT ON (expr, ...). See:
Select first row in each GROUP BY group?
Try something like...
SELECT `order_dtls`.*
FROM `order_dtls`
INNER JOIN `order_dtls` AS mirror
ON `order_dtls`.`Order_id` <> `mirror`.`Order_id`
AND `order_dtls`.`Customer_name` = `mirror`.`Customer_name`
AND DATEDIFF(`order_dtls`.`Order_date`, `mirror`.`Order_date`) = 1
The way I would think of it doing it would be to join the table the date part with itselft on the next date and joining it with the Customer_name too.
This way you can ensure that the same customer_name done an order on 2 consecutive days.
For MySQL:
SELECT distinct *
FROM order_dtls t1
INNER JOIN order_dtls t2 on
t1.Order_date = DATE_ADD(t2.Order_date, INTERVAL 1 DAY) and
t1.Customer_name = t2.Customer_name
The result you should also select it with the Distinct keyword to ensure the same customer is not displayed more than 1 time.
For postgresql:
select distinct(Customer_name) from your_table
where exists
(select 1 from your_table t1
where
Customer_name = your_table.Customer_name and Order_date = your_table.Order_date+1 )
Same for MySQL, just instead of your_table.Order_date+1 use: DATE_ADD(your_table.Order_date , INTERVAL 1 DAY)
This should work:
SELECT A.customer_name
FROM order_dtls A
INNER JOIN (SELECT customer_name, order_date FROM order_dtls) as B
ON(A.customer_name = B.customer_name and Datediff(B.Order_date, A.Order_date) =1)
group by A.customer_name
I have the following tables in SQL Server:
COMMANDLINES: ID_LINE - ID_COMMAND - ID_ARTICLE - QUANTITY
COMMAND: ID_COMMAND - ID_CLIENT - PRICE - PRINTED
CLIENT: ID_CLIENT - FULL_NAME - SSN - PH_NUM - MOBILE - USERNAME - PASSWORD
ARTICLE: ID_ARTICLE - DES - NAME - PRICE - TYPE - CURRENT_QTT - MINIMUM_QTT
ID_COMMAND from COMMANDLINES references COMMAND.ID_COMMAND
ID_CLIENT from COMMAND references CLIENT.ID_CLIENT
ID_ARTICLE from COMMANDLINES references ARTICLE.ID_ARTICLE
I need to create a view where I need to show all COMMANDLINES that have the best client (the one with the highest total of PRICE) and then I need to order them by ID_COMMAND in a descending order AND by ID_LINE in ascending order.
Sample data:
COMMANDLINE table:
COMMAND table:
Only these 2 are needed to resolve the problem. I added the other just for more information.
Sample output:
To be honest, I'm not sure if both outputs are supposed to be "output" at the same time or that I need 2 VIEWS for each output.
WHAT HAVE I DONE SO FAR:
I looked through what I could find on StackOverflow about MAX of SUM, but unfortunately, it has not helped me much in this case. I always seem to be doing something wrong.
I also found out that in order to use ORDER BY in VIEWS you need to, in this case, use TOP, but I've no idea how to apply it correctly when I need to select all of the COMMANDLINES. In one of my previous things, I used the following SELECT TOP:
create view PRODUCTS_BY_TYPE
as
select top (select count(*) from ARTICLE
where CURRENT_QTT > MINIMUM_QTT)*
from
ARTICLE
order by
TYPE
This allowed me to show all PRODUCT data where the CURRENT_QTT was more than the minimum ordering them by type, but I can't figure out for the life of me, how to apply this to my current situation.
I could start with something like this:
create view THE_BEST
as
select COMMANDLINE.*
from COMMANDLINE
But then I don't know how to apply the TOP.
I figured that first, I need to see who the best client is, by SUM-ing all of the PRICE under his ID and then doing a MAX on all of the SUM of all clients.
So far, the best I could come up with is this:
create view THE_BEST
as
select top (select count(*)
from (select max(max_price)
from (select sum(PRICE) as max_price
from COMMAND) COMMAND) COMMAND) COMMANDLINE.*
from COMMANDLINE
inner join COMMAND on COMMANDLINE.ID_COMMAND = COMMAND.ID_COMMAND
order by COMMAND.ID_COMMAND desc, COMMANDLINE.ID_LINE asc
Unfortunately, in the select count(*) the COMMAND is underlined in red (a.k.a. the 3rd COMMAND word) and it says that there is "no column specified for column 1 of COMMAND".
EDIT:
I've come up with something closer to what I want:
create view THE_BEST
as
select top (select count(*)
from (select max(total_price) as MaxPrice
from (select sum(PRICE) as total_price
from COMMAND) COMMAND) COMMAND)*
from COMMANDLINE
order by ID_LINE asc
Still missing the ordered by ID_COMMAND and I only get 1 result in the output when it should be 2.
here is some code that hopefully will show you how you can use the top-clause and also a different approche to show only the "top" :-)
/* Creating Tables*/
CREATE TABLE ARTICLE (ID_ARTICLE int,DES varchar(10),NAME varchar(10),PRICE float,TYPE int,CURRENT_QTT int,MINIMUM_QTT int)
CREATE TABLE COMMANDLINES (ID_LINE int,ID_COMMAND int,ID_ARTICLE int,QUANTITY int)
CREATE TABLE COMMAND (ID_COMMAND int, ID_CLIENT varchar(20), PRICE float, PRINTED int)
CREATE TABLE CLIENT (ID_CLIENT varchar(20), FULL_NAME varchar(50), SSN varchar(50), PH_NUM varchar(50), MOBILE varchar(50), USERNAME varchar(50), PASSWORD varchar(50))
INSERT INTO COMMANDLINES VALUES (1,1,10,20),(2,1,12,3),(3,1,2,21),(1,2,30,2),(2,2,21,5),(1,3,32,20),(2,3,21,2)
INSERT INTO COMMAND VALUES (1,'1695152D',1200,0),(2,'1695152D',500,0),(3,'2658492D',200,0)
INSERT INTO ARTICLE VALUES(1, 'A','AA',1300,0,10,5),(2,'B','BB',450,0,10,5),(30,'C','CC',1000,0,5,5),(21,'D','DD',1500,0,5,5),(32,'E','EE',1600,1,4,5),(3,'F','FF',210,2,15,5)
INSERT INTO CLIENT VALUES ('1695152D', 'DoombringerBG', 'A','123','321','asdf','asf'),('2658492D', 'tgr', 'A','123','321','asdf','asf')
GO
/* Your View-Problem*/
CREATE VIEW PRODUCTS_BY_TYPE AS
SELECT TOP 100 PERCENT *
FROM ARTICLE
WHERE CURRENT_QTT > MINIMUM_QTT -- You really don't want >= ??
ORDER BY [Type]
-- why do you need your view with an ordered output? cant your query order the data?
GO
OUTPUT:
ID_ARTICLE | DES | NAME | PRICE | TYPE | CURRENT_QTT | MINIMUM_QTT
-------------+-------+-------+-------+------+--------------+-------------
1 | A | AA | 1300 | 0 | 10 | 5
2 | B | BB | 450 | 0 | 10 | 5
3 | F | FF | 210 | 2 | 15 | 5
I hope this is what you were looking for :-)
-- your top customers
SELECT cli.FULL_NAME, SUM(c.PRICE)
FROM COMMANDLINES as cl
INNER JOIN COMMAND as c
on cl.ID_COMMAND = c.ID_COMMAND
INNER JOIN CLIENT as cli
on cli.ID_CLIENT = c.ID_CLIENT
GROUP BY cli.FULL_NAME
ORDER BY SUM(c.PRICE) DESC -- highest value first
SELECT *
FROM (
-- your top customers with a rank
SELECT cli.FULL_NAME, SUM(c.PRICE) as Price, ROW_NUMBER() OVER (ORDER BY SUM(c.PRICE) DESC) AS RowN
FROM COMMANDLINES as cl
INNER JOIN COMMAND as c
on cl.ID_COMMAND = c.ID_COMMAND
INNER JOIN CLIENT as cli
on cli.ID_CLIENT = c.ID_CLIENT
GROUP BY cli.FULL_NAME
) as a
-- only the best :-)
where RowN = 1
--considerations: what if two customers have the same value?
Output:
FULL_NAME |Price | RowN
----------------+---------+-------
DoombringerBG | 4600 | 1
Regards
tgr
===== EDITED =====
The syntax-corrention to your THE_BEST-View:
create view THE_BEST AS
SELECT TOP (
SELECT count(*) as cnt
FROM (
SELECT max(max_price) as max_price
FROM (
SELECT sum(PRICE) AS max_price
FROM COMMAND
) COMMAND
) COMMAND
)
cl.*
FROM COMMANDLINES as cl
INNER JOIN COMMAND as c
ON cl.ID_COMMAND = c.ID_COMMAND
ORDER BY c.ID_COMMAND DESC
,cl.ID_LINE ASC
Without the OVER-Clause:
SELECT TOP 1 *
FROM (
-- your top customers with a rank
SELECT cli.FULL_NAME, SUM(c.PRICE) as Price
FROM COMMANDLINES as cl
INNER JOIN COMMAND as c
on cl.ID_COMMAND = c.ID_COMMAND
INNER JOIN CLIENT as cli
on cli.ID_CLIENT = c.ID_CLIENT
GROUP BY cli.FULL_NAME
) as a
-- only the best :-)
ORDER BY Price DESC
Your PRODUCTS_BY_TYPE without PERCENT:
CREATE VIEW PRODUCTS_BY_TYPE AS
SELECT TOP (select
SUM(p.rows)
from sys.partitions as p
inner join sys.all_objects as ao
on p.object_id = ao.object_id
where ao.name = 'ARTICLE'
and ao.type = 'U')
*
FROM ARTICLE
WHERE CURRENT_QTT > MINIMUM_QTT -- You really don't want >= ??
ORDER BY [Type]
go
but to be honest - i would never use such a query in production... i only posted this because you need it for studing purposes...
It is quite likely that there is some misunderstanding between you and your teacher. You can technically have ORDER BY clause in a view definition, but it never guarantees any order of the rows in the query that uses the view, such as SELECT ... FROM your_view. Without ORDER BY in the final SELECT the order of the result set is not defined. The order of rows returned to the client by the server is determined only by the final outermost ORDER BY of the query, not by the ORDER BY in the view definition.
The purpose of having TOP in the view definition is to limit the number of returned rows somehow. For example, TOP (1). In this case ORDER BY specifies which row(s) to return.
Having TOP 100 PERCENT in a view does nothing. It doesn't reduce the number of returned rows and it doesn't guarantee any specific order of returned rows.
Having said all that, in your case you need to find one best client, so it makes sense to use TOP (1) in a sub-query.
This query would return the ID of the best client:
SELECT
TOP (1)
-- WITH TIES
ID_CLIENT
FROM COMMAND
GROUP BY ID_CLIENT
ORDER BY SUM(PRICE) DESC
If there can be several clients with the same maximum total price and you want to return data related to all of them, not just one random client, then use TOP WITH TIES.
Finally, you need to return lines that correspond to the chosen client(s):
create view THE_BEST
as
SELECT
COMMANDLINE.ID_LINE
,COMMANDLINE.ID_COMMAND
,COMMANDLINE.ID_ARTICLE
,COMMANDLINE.QUANTITY
FROM
COMMANDLINE
INNER JOIN COMMAND ON COMMAND.ID_COMMAND = COMMANDLINE.ID_COMMAND
WHERE
COMMAND.ID_CLIENT IN
(
SELECT
TOP (1)
-- WITH TIES
ID_CLIENT
FROM COMMAND
GROUP BY ID_CLIENT
ORDER BY SUM(PRICE) DESC
)
;
This is how the view can be used:
SELECT
ID_LINE
,ID_COMMAND
,ID_ARTICLE
,QUANTITY
FROM THE_BEST
ORDER BY ID_COMMAND DESC, ID_LINE ASC;
Note, that ORDER BY ID_COMMAND DESC, ID_LINE ASC has to be in the actual query, not in the view definition.
situation:
we have monthly files that get loaded into our data warehouse however instead of being replaced with old loads, these are just compiled on top of each other. the files are loaded in over a period of days.
so when running a SQL script, we would get duplicate records so to counteract this we run a union over 10-20 'customers' and selecting Max(loadID) e.g
SELECT
Customer
column 2
column 3
FROM
MyTable
WHERE
LOADID = (SELECT MAX (LOADID) FROM MyTable WHERE Customer= 'ASDA')
UNION
SELECT
Customer
column 2
column 3
FROM
MyTable
WHERE
LOADID = (SELECT MAX (LOADID) FROM MyTable WHERE Customer= 'TESCO'
The above union would have to be done for multiple customers so i was thinking surely there has to be a more efficient way.
we cant use a MAX (LoadID) in the SELECT statement as a possible scenario could entail the following;
Monday: Asda,Tesco,Waitrose loaded into DW (with LoadID as 124)
Tuesday: Sainsburys loaded in DW (with LoadID as 125)
Wednesday: New Tesco loaded in DW (with LoadID as 126)
so i would want LoadID 124 Asda & Waitrose, 125 Sainsburys, & 126 Tesco
Use window functions:
SELECT t.*
FROM (SELECT t.*, MAX(LOADID) OVER (PARTITION BY Customer) as maxLOADID
FROM MyTable t
) t
WHERE LOADID = maxLOADID;
Would a subquery to a derived table meet your needs?
select yourfields
from yourtables join
(select customer, max(loadID) maxLoadId
from yourtables
group by customer) derivedTable on derivedTable.customer = realTable.customer
and loadId = maxLoadId