I have 2 different types of records in my 'items' table (postgreSQL database). Some items have invoiceid associated, which has customer information associated. The other items in my items table do not have an invoice number associated.
I am trying to return a list of items with invoice date and customer names. The items that don't have invoice or customerer associated will also show, but those fields will just be blank. The problem is with my current sql statment. It only shows the items with invoice info associated.
select items.ItemID, items.qty, items.description, customers.firstname,
customers.lastname, invoices.InvoiceDate, items.status
from items
inner join Invoices on items.InvoiceID = Invoices.InvoiceID
inner join customers on Invoices.CustomerID = Customers.CustomerID
where Items.Status = 'ONTIME'
ORDER BY InvoiceDate asc
Any ideas how I can get all records to show, or is it even possible? The fields that don't have data are NULL, i'm not sure if that is part of the problem or not.
You want to use left outer join instead of inner join:
select i.ItemID, i.qty, i.description, c.firstname,
c.lastname, inv.InvoiceDate, i.status
from items i left outer join
Invoices inv
on i.InvoiceID = inv.InvoiceID left outer join
customers c
on inv.CustomerID = c.CustomerID
where i.Status = 'ONTIME'
order by InvoiceDate asc;
I also introduced table aliases to make the query a bit easier to read.
Related
I am querying a SQL Server database using a stored procedure.
My database tables include:
Customers
SalesOrders - Linked to the customers with an id
SalesOrderLines - Linked to the SalesOrders with an id
SalesOrderReleases - Linked to the SalesOrderLines with an id, stores the quantity on the order line that has been released and ready to manufacture, the SalesOrderLine quantity can be all on one release or split up on multiple
FinishedGoods - linked to the SalesOrderLines with an id, stores the quantity of the SalesOrderLine where manufacturing is complete, the SalesOrderLine quantity can be all on one FinishedGood entry or split up on multiple
I need to retrieve all the customers that have SalesOrderLines with SalesOrderReleases and FinishedGoods where the total quantity finished is less than the total quantity released
I have tried this SQL code but Customers appear repeatedly in the results
SELECT
Customer.ID, Customer.Name
FROM
Customer
INNER JOIN
SalesOrder ON Customer.ID = SalesOrder.CustomerID
INNER JOIN
SalesOrderLine ON SalesOrder.ID = SalesOrderLine.SalesOrderID
INNER JOIN
SalesOrderRelease ON SalesOrderLine.ID = SalesOrderRelease.SalesOrderLineID
INNER JOIN
FinishedGood ON SalesOrderLine.ID = FinishedGood.SalesOrderLineID AND FinishedGood.Quantity < SalesOrderRelease.Quantity
I am looking for a SQL code snippet that will query multiple tables the way I have described.
try this code:
SELECT Customer.ID, Customer.Name FROM Customer
INNER JOIN SalesOrder ON Customer.ID = Order.CustomerID
INNER JOIN SalesOrderLine ON Order.ID = OrderLine.OrderID
INNER JOIN
(SELECT OrderID, OrderLineID, SUM (Quantity) AS SRQuantity FROM
SalesOrderRelease GROUP BY OrderID, OrderLineID) AS SRQ
ON SRQ.OrderID = SalesOrderLine.OrderID
INNER JOIN
(SELECT OrderLineID, SUM (Quantity) AS FGQuantity FROM
FinishedGoods GROUP BY OrderLineID) AS FGQ
ON SRQ.OrderLineID = FGQ.OrderLineID
WHERE FGQ.FgQuantity < SRQ.SRQuantity
Credits to Sergey for his answer, I was able to use the sample code he provided with several slight modifications:
SELECT Customer.ID, Customer.Name FROM Customer
INNER JOIN SalesOrder ON Customer.ID = SalesOrder.CustomerID
INNER JOIN SalesOrderLine ON SalesOrder.ID = SalesOrderLine.SalesOrderID
INNER JOIN
(SELECT SalesOrderID, SalesOrderLineID, SUM (Quantity) AS SRQuantity FROM
SalesOrderRelease GROUP BY SalesOrderID, SalesOrderLineID) AS SRQ
ON SRQ.SalesOrderLineID = SalesOrderLine.SalesOrderID
LEFT JOIN
(SELECT SalesOrderLineID, SUM (Quantity) AS FGQuantity FROM
FinishedGood GROUP BY SalesOrderLineID) AS FGQ
ON SRQ.SalesOrderLineID = FGQ.SalesOrderLineID
WHERE ISNULL(FGQ.FgQuantity, 0) < SRQ.SRQuantity
The last join needed to be a Left Join
When comparing the FgQuantity and the SRQuantity in the last line, I needed to have it check for NULL values
With these modifications everythings works perfectly!
I'm having trouble with a really simple left join statement that's driving me nuts
I wanted to count the numbers of orders from each customer, that's fine, but I want to display the name, and I'm joining with the customers table and trying to select the name and it says that CustomerName is not part of an aggregate function, it's really weird.
SELECT Customers.CustomerName as 'Name',
COUNT(*) AS 'Order Count'
FROM Orders
LEFT JOIN Customers
ON Orders.CustomerID = Customers.CustomerID
GROUP BY Customers.CustomerID
Thanks for any tips.
You need to count the rows from the orders table, and the left join should be in the other direction:
SELECT c.customerid,
c.CustomerName as "Name",
COUNT(o.customerid) AS "Order Count"
FROM Customers c
LEFT JOIN Orders o ON o.CustomerID = cs.CustomerID
GROUP BY c.CustomerID, c.customername;
count() will ignore NULL values that come into the result due to the outer join so it will count the number of orders for each customers. Customers without orders will be show with a zero count.
Include CustomerName in Group BY instead of CustomerID
SELECT Customers.CustomerName as 'Name', COUNT(*) AS 'Order Count'
FROM Orders LEFT JOIN Customers ON Orders.CustomerID = Customers.CustomerID
GROUP BY Customers.CustomerName
If you are using SQL Server then try using OVER() without Group BY
SELECT Customers.CustomerName as 'Name', COUNT(*) OVER (PARTITION BY Customers.CustomerName ORDER BY Customers.CustomerName)AS 'Order Count'
FROM Orders LEFT JOIN Customers ON Orders.CustomerID = Customers.CustomerID
Modify as below. column used in group by clause should be in column queried in select clause
SELECT Customers.CustomerName as 'Name',
COUNT(*) AS 'Order Count'
FROM Orders
LEFT JOIN Customers
ON Orders.CustomerID = Customers.CustomerID
GROUP BY Customers.CustomerName
I have just reordered your query,please try this it will definitely work for you.
SELECT Customers.CustomerName as 'Name',
COUNT(*) AS 'Order Count'
FROM Customers
LEFT JOIN Orders
ON Customers.CustomerID=Orders.CustomerID
GROUP BY Customers.CustomerID
A simple approach to get all the columns in the customers table is to use a correlated subquery:
select c.*, -- or whatever columns you want
(select count(*)
from orders o
where o.CustomerID = c.CustomerID
) as order_count
from customers c;
Because this avoids the outer GROUP BY, this also has the advantage of having better performance in most databases, particularly with an index on orders(CustomerId). Plus, it returns 0 if the customer has no orders. And, it allows you to choose any or all of the columns from Customers.
The correct way to get the counts you want is to count a column from Orders:
SELECT c.CustomerName, c.CustomerID,
COUNT(o.CustomerId) AS Order_Count
FROM Customers c LEFT JOIN
Orders o
ON o.CustomerID = c.CustomerID
GROUP BY c.CustomerID, c.CustomerName;
Notes:
The Customers table goes first in the LEFT JOIN because presumably you want all rows in Customers.
Table aliases make the query easier to write and to read.
Do not use single quotes for column aliases, even if your database supports it. The best method is to choose aliases that do not need to be supported.
Include the CustomerId in the logic, just in case two customers have the same name.
Count a column from Orders so you get a count of 0 for customers with no orders.
I have a Postgres (9.1) customer database similar to:
customers.id
customers.lastname
customers.firstname
invoices.id
invoices.customerid
invoices.total
invoicelines.id
invoicelines.invoiceid
invoicelines.itemcode
invoicelines.price
I built a search which lists all customers who have purchased a certain item (say 'abc').
Select * from customers WHERE customers.id IN
(Select invoices.customerid FROM invoices WHERE invoices.id IN
(Select invoicelines.invoiceid FROM invoicelines WHERE
invoicelines.itemcode = 'abc')
)
The search works fine and brings up the correct customers but takes about 10 seconds or so on a database of 2 million invoices and 2 million line items.
I was wondering if there was another approach that could trim that down a bit.
An alternative is to use EXISTS:
Select *
from customers
WHERE EXISTS (
Select invoices.customerid
FROM invoices
JOIN invoicelines
ON invoicelines.invoiceid = invoices.id AND
invoicelines.itemcode = 'abc' AND
customers.id = invoices.customerid)
You might switch to using exists instead. I suspect that this might work well:
Select c.*
from customers c
where exists (Select 1
from invoices i join
invoicelines il
on i.id = il.invoiceid and il.itemcode = 'abc'
where c.id = i.customerid
);
For this, you want to be sure you have the right indexes: invoices(customerid, id) and invoicelines(invoiceid, itemcode).
Do you want all of the rows and columns in customer where the itemcode for that customer's item is 'abc'? If you join on the customerid then you can find all of the customer information for those items. If you have duplicates within that list you can use DISTINCT which will only give you one entry per customerID.
SELECT
DISTINCT [List of customer columns]
FROM
customers
INNER JOIN
invoicelines
ON
customers.customerid = invoicelines.customerid
AND
invoicelines.itemcode = 'abc'
when I use below code, I get the data of customers who ordered "Planned" or 'obsolete' products, but I want to get data of the customers who ordered both type, changing 'or' to 'and' does not work... please help
SELECT DISTINCT customers.CUST_EMAIL
,ORDERS.ORDER_ID
,PRODUCT_INFORMATION.PRODUCT_NAME
,PRODUCT_INFORMATION.PRODUCT_STATUS
FROM PRODUCT_INFORMATION
INNER JOIN ORDER_ITEMS ON PRODUCT_INFORMATION.PRODUCT_ID = ORDER_ITEMS.PRODUCT_ID
INNER JOIN ORDERS ON ORDER_ITEMS.ORDER_ID = ORDERS.ORDER_ID
INNER JOIN CUSTOMERS ON CUSTOMERS.CUSTOMER_ID = ORDERS.CUSTOMER_ID
WHERE PRODUCT_INFORMATION.PRODUCT_STATUS = 'planned'
OR PRODUCT_INFORMATION.PRODUCT_STATUS = 'obsolete'
ORDER BY CUSTOMERS.CUST_EMAIL;
I'm guessing that you want the following. If you want to get correct answer, rather than guesses, please provide a good representative set of sample data and your expected result based on that sample data.
First part of the query returns Customers that ordered planned products, second part of the query returns Customers that ordered obsolete products. INTERSECT operator returns only those that have ordered both planned and obsolete products.
You don't need explicit DISTINCT any more, because INTERSECT would do it anyway.
I've removed PRODUCT_INFORMATION.PRODUCT_STATUS from the list of returned columns, because with it the result set would be always empty.
I removed ORDERS.ORDER_ID and PRODUCT_INFORMATION.PRODUCT_NAME from result as well. I don't know what should be the correct query, but it is likely that INTERSECT should be done just on CUSTOMER_ID and then, once you get the list of IDs, you can join other tables to it fetching other related details if needed.
The performance of this method is beyond the scope of the question.
SELECT
CUSTOMERS.CUSTOMER_ID
,customers.CUST_EMAIL
FROM
PRODUCT_INFORMATION
INNER JOIN ORDER_ITEMS ON PRODUCT_INFORMATION.PRODUCT_ID = ORDER_ITEMS.PRODUCT_ID
INNER JOIN ORDERS ON ORDER_ITEMS.ORDER_ID = ORDERS.ORDER_ID
INNER JOIN CUSTOMERS ON CUSTOMERS.CUSTOMER_ID = ORDERS.CUSTOMER_ID
WHERE PRODUCT_INFORMATION.PRODUCT_STATUS = 'planned'
INTERSECT
SELECT
CUSTOMERS.CUSTOMER_ID
,customers.CUST_EMAIL
FROM
PRODUCT_INFORMATION
INNER JOIN ORDER_ITEMS ON PRODUCT_INFORMATION.PRODUCT_ID = ORDER_ITEMS.PRODUCT_ID
INNER JOIN ORDERS ON ORDER_ITEMS.ORDER_ID = ORDERS.ORDER_ID
INNER JOIN CUSTOMERS ON CUSTOMERS.CUSTOMER_ID = ORDERS.CUSTOMER_ID
WHERE PRODUCT_INFORMATION.PRODUCT_STATUS = 'obsolete'
ORDER BY CUST_EMAIL
without the script for you tables it's difficult to build a test case and a working query; i'll try with this step:
select order_id from (
SELECT customers.CUSTOMER_ID
,sum(decode(PRODUCT_INFORMATION.PRODUCT_STATUS, 'obsolete', 1, 0)) obsolete
,sum(decode(PRODUCT_INFORMATION.PRODUCT_STATUS, 'planned', 1, 0)) planned
FROM PRODUCT_INFORMATION
INNER JOIN ORDER_ITEMS ON PRODUCT_INFORMATION.PRODUCT_ID = ORDER_ITEMS.PRODUCT_ID
INNER JOIN ORDERS ON ORDER_ITEMS.ORDER_ID = ORDERS.ORDER_ID
INNER JOIN CUSTOMERS ON CUSTOMERS.CUSTOMER_ID = ORDERS.CUSTOMER_ID
WHERE PRODUCT_INFORMATION.PRODUCT_STATUS = 'planned'
OR PRODUCT_INFORMATION.PRODUCT_STATUS = 'obsolete'
group by customers.CUSTOMER_ID)
where obsolete>1 and planned>1
This query should return all the customer id that have items in orders with both the product status (the different product status may be in different orders), if you want to retrieve orders that have products with both status you must change the query removing customer.customer_id and adding orders.order_id. If you provide some script with sample data we can provide a better answer
Here is how I contructed the step-by-step:
M1. create a sub-query that will return CustomerId and total invoiced for that customer
M2. A second subquery that will give a list of distinct ProductIDs (along with product SKUs) and CustomerIDs.
M3. The M1 and M2 subqueries will be joined to make association between customer totals and products (for the same CustomerId).
M4. The query M3 will be fed to the final query that will just find the top 5 products.
I'm stuck on creating the distinct ProductID and customerID because they would have to be in aggregate functions in order to make them distinct.
Attached is an image that is the erwin diagram which helps understand the system.
If you can help me with M1-M4, I will greatly appreciate it. I'm not a programmer by trade but a business analyst.
--M1--
select C.CustomerId, COUNT(I.InvoiceId) TotalNumInvoices
from Customer C
JOIN Invoice I ON (I.CustomerId = C.CustomerId)
group by C.CustomerId
--M2: Incomplete--
select P.ProductID, P.SKU, C.CustomerID
from Product P
JOIN InvoiceLine IL ON (IL.ProductId = P.ProductId)
JOIN Invoice I ON (IL.InvoiceId = I.InvoiceId)
JOIN Customer C ON (C.CustomerId = I.CustomerId)
you can also use the DISTINCT keyword your select clause in order to get unique values. Try this for m2:
select DISTINCT p.productID, p.sku, i.customerID
from invoice i INNER JOIN invoiceLine il
ON i.invoiceID = il.invoiceID
JOIN product p
ON il.productID = p.productID;