Inner join returns too many rows - sql

I a having an issue joining two tables in order to return just one column from the other.
SELECT om.*, cm.Sales_Stage
FROM dbo.OM_Table1 om
JOIN dbo.Criteria_Matters cm ON cm.clientCorporationID = om.ClientCorporationID
ORDER BY om.ClientCorporationID
I want to include the Sales_Stage from my CM table but the join causes the result set to return 14k+ rows instead of the ~7k that is returned without the join.
Is there anyway to just bring in this additional column without blowing up the query?

You can use a subquery... note that this may not correctly select the sales_stage you want as you have multiple entries in Criteria_Matters per ClientCorporationID. You probably need an order by on the subquery.
SELECT om.*,
(SELECT TOP 1 cm.Sales_Stage
FROM dbo.Criteria_Matters cm
WHERE cm.clientCorporationID = om.ClientCorporationID) AS Sales_Stage
ORDER BY om.ClientCorporationID
... I'm assuming the om.* was just for the example. it is typically best practice to NOT do that in production.
If you intended to see the differences you may want to do something like this instead...
SELECT om.*, cm.Sales_Stage, cm.Criteria_MatterID
FROM dbo.OM_Table1 om
JOIN dbo.Criteria_Matters cm ON cm.clientCorporationID = om.ClientCorporationID
ORDER BY om.ClientCorporationID

Just guessing since there is no information on the structure of your tables, but the problem is likely that the Criteria_Matters table has many records for a given clientCorporationID. So it will duplicate every record in OM_Table1 based on the number of matching Criteria_Matters.ClientCorporationID records.
There are a few ways to deal with this - one way would be to use an inline view instead of joining to the full Criteria_Matters table.
If you add an inline view and GROUP BY Criteria_Matters.ClientCorporationID - you are guaranteed that there will be only one record per ClientCorporationID in the joined table - and you will not get duplicated records. Of course since you are grouping by clientCorporationID, you need to apply some aggregate function to Sales_Stage. If you just pick MAX(Sales_Stage), you will get whatever the maximum value is. If you know Sales_Stage is the same for every given clientCorporationID - you are all set. The SQL will look something like the following:
SELECT om.*, cm.Sales_Stage
FROM dbo.OM_Table1 om
INNER JOIN
(
SELECT clientCorporationID, MAX(Sales_Stage) AS Sales_Stage
FROM dbo.Criteria_Matters
GROUP BY clientCorporationID
) cm ON cm.clientCorporationID = om.ClientCorporationID
ORDER BY om.ClientCorporationID
However, if there are different Sales_Stage values for a given clientCorporationID in the Criteria_Matters table - you can group by both clientCorporationID and Sales_Stage. When you do this, you will now get OM_Table1 records duplicated - but only for each unique Sales_Stage corresponding to a ClientCorporationID in Criteria_Matters. The SQL would look like this:
SELECT om.*, cm.Sales_Stage
FROM dbo.OM_Table1 om
INNER JOIN
(
SELECT clientCorporationID, Sales_Stage
FROM dbo.Criteria_Matters
GROUP BY clientCorporationID, Sales_Stage
) cm ON cm.clientCorporationID = om.ClientCorporationID
ORDER BY om.ClientCorporationID
Good luck!

Related

Query with Left outer join and group by returning duplicates

To begin with, I have a table in my db that is fed with SalesForce info. When I run this example query it returns 2 rows:
select * from SalesForce_INT_Account__c where ID_SAP_BAYER__c = '3783513'
When I run this next query on the same table I obtain one of the rows, which is what I need:
SELECT MAX(ID_SAP_BAYER__c) FROM SalesForce_INT_Account__c where ID_SAP_BAYER__c = '3783513' GROUP BY ID_SAP_BAYER__c
Now, I have another table (PedidosEspecialesZarateCabeceras) which has a field (NroClienteDireccionEntrega) that I can match with the field I've been using in the SalesForce table (ID_SAP_BAYER__c). This table has a key that consists of just 1 field (NroPedido).
What I need to do is join these 2 tables to obtain a row from PedidosEspecialesZarateCabeceras with additional fields coming from the SalesForce table, and in case those additional fields are not available, they should come as NULL values, so for that im using a LEFT OUTER JOIN.
The problem is, since I have to match NroClienteDireccionEntrega and ID_SAP_BAYER__c and there's 2 rows in the salesforce table with the same ID_SAP_BAYER__c, my query returns 2 duplicate rows from PedidosEspecialesZarateCabeceras (They both have the same NroPedido).
This is an example query that returns duplicates:
SELECT
cab.CUIT AS CUIT,
convert(nvarchar(4000), cab.NroPedido) AS NroPedido,
sales.BillingCity__c as Localidad,
sales.BillingState__c as IdProvincia,
sales.BillingState__c_Desc as Provincia,
sales.BillingStreet__c as Calle,
sales.Billing_Department__c as Distrito,
sales.Name as RazonSocial,
cab.NroCliente as ClienteId
FROM PedidosEspecialesZarateCabeceras AS cab WITH (NOLOCK)
LEFT OUTER JOIN
SalesForce_INT_Account__c AS sales WITH (NOLOCK) ON
cab.NroClienteDireccionEntrega = sales.ID_SAP_BAYER__c
and sales.ID_SAP_BAYER__c in
( SELECT MAX(ID_SAP_BAYER__c)
FROM SalesForce_INT_Account__c
GROUP BY ID_SAP_BAYER__c
)
WHERE cab.NroPedido ='5320'
Even though the join has MAX and Group By, this returns 2 duplicate rows with different SalesForce information (Because of the 2 salesforce rows with the same ID_SAP_BAYER__c), which should not be possible.
What I need is for the left outer join in my query to pick only ONE of the salesforce rows to prevent duplication like its happening right now. For some reason the select max with the group by is not working.
Maybe I should try to join this tables in a different way, can anyone give me some other ideas on how to join the two tables to return just 1 row? It doesnt matter if the SalesForce row that gets picked out of the 2 isn't the correct one, I just need it to pick one of them.
Your IN clause is not actually doing anything, since...
SELECT MAX(ID_SAP_BAYER__c)
FROM SalesForce_INT_Account__c
GROUP BY ID_SAP_BAYER__c
... returns all possible IDSAP_BAYER__c values. (The GROUP BY says you want to return one row per unique ID_SAP_BAYER__c and then, since your MAX is operating on exactly one unique value per group, you simply return that value.)
You will want to change your query to operate on a value that is actually different between the two rows you are trying to differentiate (probably the MAX(ID) for the relevant ID_SAP_BAYER__c). Plus, you will want to link that inner query to your outer query.
You could probably do something like:
...
LEFT OUTER JOIN
SalesForce_INT_Account__c sales
ON cab.NroClienteDireccionEntrega = sales.ID_SAP_BAYER__c
and sales.ID in
(
SELECT MAX(ID)
FROM SalesForce_INT_Account__c sales2
WHERE sales2.ID_SAP_BAYER__c = cab.NroClienteDireccionEntrega
)
WHERE cab.NroPedido ='5320'
By using sales.ID in ... SELECT MAX(ID) ... instead of sales.ID_SAP_BAYER__c in ... SELECT MAX(ID_SAP_BAYER__c) ... this ensures you only match one of the two rows for that ID_SAP_BAYER__c. The WHERE sales2.ID_SAP_BAYER__c = cab.NroClienteDireccionEntrega condition links the inner query to the outer query.
There are multiple ways of doing the above, especially if you don't care which of the relevant rows you match on. You can use the above as a starting point and make it match your preferred style.
An alternative might be to use OUTER APPLY with TOP 1. Something like:
SELECT
...
FROM PedidosEspecialesZarateCabeceras AS cab
OUTER APPLY(
SELECT TOP 1 *
FROM SalesForce_INT_Account__c s1
WHERE cab.NroClienteDireccionEntrega = s1.ID_SAP_BAYER__c
) sales
WHERE cab.NroPedido ='5320'
Without an ORDER BY the match that TOP 1 chooses will be arbitrary, but I think that's what you want anyway. (If not, you could add an ORDER BY).

Complex SQL View with Joins & Where clause

My SQL skill level is pretty basic. I have certainly written some general queries and done some very generic views. But once we get into joins, I am choking to get the results that I want, in the view I am creating.
I feel like I am almost there. Just can't get the final piece
SELECT dbo.ics_supplies.supplies_id,
dbo.ics_supplies.old_itemid,
dbo.ics_supplies.itemdescription,
dbo.ics_supplies.onhand,
dbo.ics_supplies.reorderlevel,
dbo.ics_supplies.reorderamt,
dbo.ics_supplies.unitmeasure,
dbo.ics_supplies.supplylocation,
dbo.ics_supplies.invtype,
dbo.ics_supplies.discontinued,
dbo.ics_supplies.supply,
dbo.ics_transactions.requsitionnumber,
dbo.ics_transactions.openclosed,
dbo.ics_transactions.transtype,
dbo.ics_transactions.originaldate
FROM dbo.ics_supplies
LEFT OUTER JOIN dbo.ics_orders
ON dbo.ics_supplies.supplies_id = dbo.ics_orders.suppliesid
LEFT OUTER JOIN dbo.ics_transactions
ON dbo.ics_orders.requisitionnumber =
dbo.ics_transactions.requsitionnumber
WHERE ( dbo.ics_transactions.transtype = 'PO' )
When I don't include the WHERE clause, I get 17,000+ records in my view. That is not correct. It's doing this because we are matching on a 1 to many table. Supplies table is 12,000 records. There should always be 12,000 records. Never more. Never less.
The pieces that I am missing are:
I only need ONE matching record from the ICS_Transactions Table. Ideally, the one that I want is the most current 'ICS_Transactions.OriginalDate'.
I only want the ICS_Transactions Table fields to populate IF ICS_Transacions.Type = 'PO'. Otherwise, these fields should remain null.
Sample code or anything would help a lot. I have done a lot of research on joins and it's still very confusing to get what I need for results.
EDIT/Update
I feel as if I asked my question in the wrong way, or didn't give a good overall view of what I am asking. For that, I apologize. I am still very new to SQL, but trying hard.
ICS_Supplies Table has 12,810 records
ICS_Orders Table has 3,666 records
ICS_Transaction Table has 4,701 records
In short, I expect to see a result of 12,810 records. No more and no less. I am trying to create a View of ALL records from the ICS_Supplies table.
Not all records in Supply Table are in Orders and or Transaction Table. But still, I want to see all 12,810 records, regardless.
My users have requested that IF any of these supplies have an open PO (ICS_Transactions.OpenClosed = 'Open' and ICS_Transactions.InvType = 'PO') Then, I also want to see additional fields from ICS_Transactions (ICS_Transactions.OpenClosed, ICS_Transactions.InvType, ICS_Transactions.OriginalDate, ICS_Transactions.RequsitionNumber).
If there are no open PO's for supply record, then these additional fields should be blank/null (regardless to what data is in these added fields, they should display null if they don't meet the criteria).
The ICS_Orders Table is nly needed to hop from the ICS_Supplies to the ICS_Transactions (I first, need to obtain the Requisition Number from the Orders field, if there is one).
I am sorry if I am not doing a good job to explain this. Please ask if you need clarification.
Here's a simplified version of Ross Bush's answer (It removes a join from the CTE to keep things more focussed, speed things up, and cut down the code).
;WITH
ordered_ics_transactions AS
(
SELECT
*,
ROW_NUMBER() OVER (PARTITION BY requisitionnumber
ORDER BY originaldate DESC
)
AS seq_id
FROM
dbo.ics_transactions
)
SELECT
s.supplies_id, s.old_itemid,
s.itemdescription, s.onhand,
s.reorderlevel, s.reorderamt,
s.unitmeasure, s.supplylocation,
s.invtype, s.discontinued,
s.supply,
t.requsitionnumber, t.openclosed,
t.transtype, t.originaldate
FROM
dbo.ics_supplies AS s
LEFT OUTER JOIN
dbo.ics_orders AS o
ON o.supplies_id = s.suppliesid
LEFT OUTER JOIN
ordered_ics_transactions AS t
ON t.requisitionnumber = o.requisitionnumber
AND t.transtype = 'PO'
AND t.seq_id = 1
This will only join the most recent transaction record for each requisitionnumber, and only if it has transtype = 'PO'
IF you want to reverse that (joining only transaction records that have transtype = 'PO', and of those only the most recent one), then move the transtype = 'PO' filter to be a WHERE clause inside the ordered_ics_transactions CTE.
You can possibly work with the query below to get what you need.
1. I only need ONE matching record from the ICS_Transactions Table. Ideally, the one that I want is the most current 'ICS_Transactions.OriginalDate'.
I would solve this by creating a CTE with all the ICS_Transaction fields needed in the query, rank-ordered by OPriginalDate, partitioned by suppliesid.
2. I only want the ICS_Transactions Table fields to populate IF ICS_Transacions.Type = 'PO'. Otherwise, these fields should remain null.
If you move the condition from the WHERE clause to the LEFT JOIN then ICS_Transactions not matching the criteria will be peeled and replaced with null values with the rest of the query records.
;
WITH ReqNumberRanked AS
(
SELECT
dbo.ICS_Orders.SuppliesID,
dbo.ICS_Transactions.RequisitionNumber,
dbo.ICS_Transactions.TransType,
dbo.ICS_Transactions.OriginalDate,
dbo.ICS_Transactions.OpenClosed,
RequisitionNumberRankReversed = RANK() OVER(PARTITION BY dbo.ICS_Orders.SuppliesID, dbo.ICS_Transactions.RequisitionNumber ORDER BY dbo.ICS_Transactions.OriginalDate DESC)
FROM
dbo.ICS_Orders
LEFT OUTER JOIN dbo.ICS_Transactions ON dbo.ICS_Orders.RequisitionNumber = dbo.ICS_Transactions.RequsitionNumber
)
SELECT
dbo.ICS_Supplies.Supplies_ID, dbo.ICS_Supplies.Old_ItemID,
dbo.ICS_Supplies.ItemDescription, dbo.ICS_Supplies.OnHand,
dbo.ICS_Supplies.ReorderLevel, dbo.ICS_Supplies.ReorderAmt,
dbo.ICS_Supplies.UnitMeasure,
dbo.ICS_Supplies.SupplyLocation, dbo.ICS_Supplies.InvType,
dbo.ICS_Supplies.Discontinued, dbo.ICS_Supplies.Supply,
ReqNumberRanked.RequsitionNumber,
ReqNumberRanked.OpenClosed,
ReqNumberRanked.TransType,
ReqNumberRanked.OriginalDate
FROM
dbo.ICS_Supplies
LEFT OUTER JOIN dbo.ICS_Orders ON dbo.ICS_Supplies.Supplies_ID = dbo.ICS_Orders.SuppliesID
LEFT OUTER JOIN ReqNumberRanked ON ReqNumberRanked.RequisitionNumber = dbo.ICS_Transactions.RequsitionNumber
AND (ReqNumberRanked.TransType = 'PO')
AND ReqNumberRanked.RequisitionNumberRankReversed = 1

Specifying SELECT, then joining with another table

I just hit a wall with my SQL query fetching data from my MS SQL Server.
To simplify, say i have one table for sales, and one table for customers. They each have a corresponding userId which i can use to join the tables.
I wish to first SELECT from the sales table where say price is equal to 10, and then join it on the userId, in order to get access to the name and address etc. from the customer table.
In which order should i structure the query? Do i need some sort of subquery or what do i do?
I have tried something like this
SELECT *
FROM Sales
WHERE price = 10
INNER JOIN Customers
ON Sales.userId = Customers.userId;
Needless to say this is very simplified and not my database schema, yet it explains my problem simply.
Any suggestions ? I am at a loss here.
A SELECT has a certain order of its components
In the simple form this is:
What do I select: column list
From where: table name and joined tables
Are there filters: WHERE
How to sort: ORDER BY
So: most likely it was enough to change your statement to
SELECT *
FROM Sales
INNER JOIN Customers ON Sales.userId = Customers.userId
WHERE price = 10;
The WHERE clause must follow the joins:
SELECT * FROM Sales
INNER JOIN Customers
ON Sales.userId = Customers.userId
WHERE price = 10
This is simply the way SQL syntax works. You seem to be trying to put the clauses in the order that you think they should be applied, but SQL is a declarative languages, not a procedural one - you are defining what you want to occur, not how it will be done.
You could also write the same thing like this:
SELECT * FROM (
SELECT * FROM Sales WHERE price = 10
) AS filteredSales
INNER JOIN Customers
ON filteredSales.userId = Customers.userId
This may seem like it indicates a different order for the operations to occur, but it is logically identical to the first query, and in either case, the database engine may determine to do the join and filtering operations in either order, as long as the result is identical.
Sounds fine to me, did you run the query and check?
SELECT s.*, c.*
FROM Sales s
INNER JOIN Customers c
ON s.userId = c.userId;
WHERE s.price = 10

Getting way more results than expected in SQL left join query

My code is such:
SELECT COUNT(*)
FROM earned_dollars a
LEFT JOIN product_reference b ON a.product_code = b.product_code
WHERE a.activity_year = '2015'
I'm trying to match two tables based on their product codes. I would expect the same number of results back from this as total records in table a (with a year of 2015). But for some reason I'm getting close to 3 million.
Table a has about 40,000,000 records and table b has 2000. When I run this statement without the join I get 2,500,000 results, so I would expect this even with the left join, but somehow I'm getting 300,000,000. Any ideas? I even refered to the diagram in this post.
it means either your left join is using only part of foreign key, which causes row multiplication, or there are simply duplicate rows in the joined table.
use COUNT(DISTINCT a.product_code)
What is the question are are trying to answer with the tsql?
instead of select count(*) try select a.product_code, b.product_code. That will show you which records match and which don't.
Should also add a where b.product_code is not null. That should exclude the records that don't match.
b is the parent table and a is the child table? try a right join instead.
Or use the table's unique identifier, i.e.
SELECT COUNT(a.earned_dollars_id)
Not sure what your datamodel looks like and how it is structured, but i'm guessing you only care about earned_dollars?
SELECT COUNT(*)
FROM earned_dollars a
WHERE a.activity_year = '2015'
and exists (select 1 from product_reference b ON a.product_code = b.product_code)

SQL count - first time

I am learning SQL (bit by bit!) trying to perform a query on our database and adding in a count function to show the total orders that appear against a customers id by counting in a inner join query.
Somehow it is pooling all the data together onto one customer with the count function though.
Can someone please suggest where I am going wrong?
SELECT tbl_customers.*, tbl_stateprov.stprv_Name, tbl_custstate.CustSt_Destination, COUNT(order_id) as total
FROM tbl_stateprov
INNER JOIN (tbl_customers
INNER JOIN (tbl_custstate
INNER JOIN tbl_orders ON tbl_orders.order_CustomerID = tbl_custstate.CustSt_Cust_ID)
ON tbl_customers.cst_ID = tbl_custstate.CustSt_Cust_ID)
ON tbl_stateprov.stprv_ID = tbl_custstate.CustSt_StPrv_ID
WHERE tbl_custstate.CustSt_Destination='BillTo'
AND cst_LastName LIKE '#URL.Alpha#%'
You need a GROUP BY clause in this statement in order to get what you want. You need to figure out what level you want to group it by in order to select which fields to add to the group by clause. If you just wanted to see it on a per customer basis, and the customers table had an id field, it would look like this (at the very end of your sql):
GROUP BY tbl_customers.id
Now you can certainly group by more fields, it just depends how you want to slice the results.
In your select statement you are using format like tableName.ColumnName but not for COUNT(order_id)
It should be COUNT(tableOrAlias.order_id)
Hope that helps.
As you are new to SQL it might also be worth considering the readability of your joins - the nested / bracketed joins you mentioned above are quite hard to read, and I would also personally alias your tables to make the query that bit more accessible:
SELECT
tbl_customers.customer_id
,tbl_stateprov.stprv_Name
,tbl_custstate.CustSt_Destination
,COUNT(order_id) as total
FROM tbl_stateprov statep
INNER JOIN tbl_custstate state ON statep.stprv_ID = state.CustSt_StPrv_ID
INNER JOIN tbl_customers customer ON customer.cst_ID = state.CustSt_Cust_ID
INNER JOIN tbl_orders orders ON orders.order_CustomerID = state.CustSt_Cust_ID
WHERE tbl_custstate.CustSt_Destination='BillTo'
AND cst_LastName LIKE '#URL.Alpha#%'
GROUP BY
tbl_customers.customer_id
,tbl_stateprov.stprv_Name
,tbl_custstate.CustSt_Destination
--And any other columns you want to include the count for