What is 'keyword' is missing from this query? - sql

This is what I have;
SELECT c.customerFN, c.customerEmail, p.productName,
SUM(p.unitsonstock + p.unitsordered) AS "All Units"
FROM customer c
INNER JOIN order o
WHERE c.customerID=o.customerID
INNER JOIN orderDetails d
WHERE o.orderID=d.orderID
INNER JOIN product p
WHERE p.productCode=l.productCode
WHERE orderDate <= '2015-03-15'
ORDER BY productName;
When I enter this the database throws a "missing keyword" error at the fourth line. Could you tell me what it is that I'm missing

Instead of WHERE in line 5, 7 and 9 you need to use ON. You are also using function SUM, but there is no GROUP BY. Change your query like this:
SELECT c.customerFN, c.customerEmail, p.productName,
SUM(p.unitsonstock + p.unitsordered) AS "All Units"
FROM customer c
INNER JOIN order o
ON c.customerID=o.customerID
INNER JOIN orderDetails d
ON o.orderID=d.orderID
INNER JOIN product p
ON p.productCode=l.productCode
WHERE orderDate <= '2015-03-15'
GROUP BY c.customerFN, c.customerEmail, p.productName
ORDER BY p.productName;

JOIN is performed using the ON clause, not with a WHERE:
...
FROM customer c
INNER JOIN order o ON c.customerID=o.customerID
INNER JOIN orderDetails d ON o.orderID=d.orderID
INNER JOIN product p ON p.productCode=d.productCode
WHERE orderDate <= '2015-03-15'
...
The WHERE clause that comes after join should be used like you have it in your query.
Apart from the problem with the JOIN there is also a problem using SUM without grouping. You probably want something like:
SELECT c.customerFN, c.customerEmail, p.productName,
SUM(p.unitsinstock + p.unitsordered) AS "All Units"
FROM customer c
INNER JOIN order o ON c.customerID=o.customerID
INNER JOIN orderDetails d ON o.orderID=d.orderID
INNER JOIN product p ON p.productCode=d.productCode
WHERE orderDate <= '2015-03-15'
GROUP BY customerFN, customerEmail, productName
ORDER BY p.productName;
Use of SUM function implies a GROUP BY clause. Every column selected that is not part of an aggregate function like SUM must be present in the GROUP BY clause.

Related

How to group results from a column together

so... i want to find out the top 5 customers that spent the most on 1992 Ferrari 360 Spider red from my dataset
This is the query responding to the question above:
select C.customerNumber, C.customerName, P.productName, sum(ODF.priceEach) from orderDetailFacts ODF
left join Customers C on ODF.customerNumber = C.customerNumber
left join Products P on ODF.productCode = P.productCode
where P.productName like '%1992 Ferrari%'
group by C.customerNumber, C.customerName, P.productName, ODF.priceEach
order by sum(ODF.priceEach) desc
limit 5
The result that i got back is: [https://i.stack.imgur.com/rowRY.png] (There are more results than the screenshot)
However, the problem i have is that i am unable to group for e.g Mini Gifts Distributors Ltd(row 5 and 6) from the customerName column together so that the priceEach column will be the sum.
So it means that row 5 and 6 will be joined together and the priceEach column will be 386.09 instead of 196.43 and 189.66 separately.
Is there a solution to this?
I think you want one row per customer/product. But you are including the price as well. So, fix the GROUP BY:
select C.customerNumber, C.customerName, P.productName, sum(ODF.priceEach)
from orderDetailFacts ODF join
Customers C
on ODF.customerNumber = C.customerNumber join
Products P
on ODF.productCode = P.productCode
where P.productName like '%1992 Ferrari%'
group by C.customerNumber, C.customerName, P.productName;
Note the changes:
ODF.priceEach is removed from the GROUP BY.
You are requiring matches between the tables, so LEFT JOIN is not appropriate.
Remove ODF.priceEach from group by clause since you are aggregating this column
select C.customerNumber, C.customerName, P.productName, sum(ODF.priceEach) from orderDetailFacts ODF
left join Customers C on ODF.customerNumber = C.customerNumber
left join Products P on ODF.productCode = P.productCode
where P.productName like '%1992 Ferrari%'
group by C.customerNumber, C.customerName, P.productName

Query returns cartesian product when not expected

Task: Select all orders having products belonging to ‘Sea Food’ category.
Result: OrderNo, OrderDate, Product Name
I write this query but it returns Cartesian products.
select o.orderid, o.orderdate as "Order Date", p.productname , ct.categoryname from orders o,
order_details od , products p , customers c ,categories ct
where
od.orderid = o.orderid and p.productid = od.productid and ct.categoryid = p.categoryid
and ct.categoryname = 'Seafood';
Question: What is wrong with my query ?
You're doing a CROSS JOIN on customers table since you forgot to specify the connection. This is why you should use explicit JOIN syntax rather than old syntax using commas in WHERE clause.
After translating your query into explicit syntax, you will see that there is no WHERE condition involving customers table:
select
o.orderid,
o.orderdate as "Order Date",
p.productname,
ct.categoryname
from
orders o,
inner join order_details od on od.orderid = o.orderid
inner join products p on p.productid = od.productid
inner join categories ct on ct.categoryid = p.categoryid
cross join customers c -- either you don't need this table, or you need to specify conditions
where
ct.categoryname = 'Seafood'
Basically the reason you got it was that your where clause omitted join condition involving customers table, so you were left with:
from (...), customers -- cross join when joining condition not applied in where clause

Insufficient output from SQL query

I'm using the northwind db: http://dev.assets.neo4j.com.s3.amazonaws.com/wp-content/uploads/Northwind_diagram.jpg
I have to output all orders placed by CustomerID ALFKI with more than one unique product. I get the correct orders out, but I can't figure out why it's only printing one product name per order.
My query:
SELECT a.OrderID, p.ProductName
FROM Products p
INNER JOIN 'Order Details' a
ON (p.ProductID = a.ProductID)
INNER JOIN Orders b
ON (a.OrderID = b.OrderID)
WHERE (b.CustomerID = 'ALFKI')
GROUP BY a.OrderID
HAVING COUNT(DISTINCT a.ProductID) > 1
You need the GROUP BY and HAVING to be part of a subquery, with your primary query selecting the detail using the list of OrderIDs returned from the subquery as filter criteria. Try the following syntax for T-SQL:
SELECT
a.OrderID,
p.ProductName
FROM
Products p
INNER JOIN [Order Details] a
ON (p.ProductID = a.ProductID)
INNER JOIN Orders b
ON (a.OrderID = b.OrderID)
WHERE
a.OrderID IN
(
SELECT a.OrderID
FROM [Order Details] a
INNER JOIN Orders b
ON (a.OrderID = b.OrderID)
WHERE (b.CustomerID = 'ALFKI')
GROUP BY a.OrderID
HAVING COUNT(DISTINCT a.ProductID) > 1
)

Left Join in Oracle SQL

I was going through an example of LEFT JOIN on w3schools.com.
http://www.w3schools.com/sql/sql_join_left.asp
SELECT Customers.CustomerName, Orders.OrderID
FROM Customers
LEFT JOIN Orders
ON Customers.CustomerID=Orders.CustomerID
ORDER BY Customers.CustomerName;
The above query will return me all customers with No Orders as NULL Order ID+ All customers having Orders with their Order Ids
How should I modify this query so that it returns All Customers with No Orders + All Customers having Orders with Order date as '1996-09-18'
Thanks in advance.
If you want customers with no orders and those with a specific order date, then you want a WHERE clause:
SELECT c.CustomerName, o.OrderID
FROM Customers c LEFT JOIN
Orders o
ON c.CustomerID = o.CustomerID
WHERE (o.CustomerID is NULL) OR (o.OrderDate = DATE '1996-09-18)
ORDER BY c.CustomerName;
If you wanted all customers with their order on that date (if they have one), then you would move the condition to the ON clause:
SELECT c.CustomerName, o.OrderID
FROM Customers c LEFT JOIN
Orders o
ON c.CustomerID = o.CustomerID AND o.OrderDate = DATE '1996-09-18
ORDER BY c.CustomerName;
Note the difference: the first filters the customers. The second only affects what order gets shown (and NULL will often be shown).

SQL Query on SQL Server 2008

I'm trying to get only customers that ordered both a "Gas Range" and a "Washer". I'm getting Customers who ordered a "Gas Range" and not a "Washer" and customers with both. I need the customer that meets both conditions. I'm close but a little stuck. Below is the query that I have so far. Please let me know if you need more information.
My Tables - CUSTOMER(CUST_NUM, CUST_NAME), ORDER_LINE(ORDER_NUM, PART_NUM), ORDERS(ORDER_NUM, CUST_NUM), PART(PART_NUM, PART_DESCRIPTION)
SELECT C.CUST_NAME AS [Customer(s) that ordered a Gas Range and Washer]
FROM CUSTOMER C
INNER JOIN ORDERS O
ON C.CUST_NUM = O.CUST_NUM
INNER JOIN ORDER_LINE OL
ON O.ORDER_NUM = OL.ORDER_NUM
INNER JOIN PART P
ON OL.PART_NUM = P.PART_NUM
WHERE P.PART_DESCRIPTION IN ('GasRange','Washer')
GROUP BY C.CUST_NAME
try the following
SELECT C.CUST_NAME AS [Customer(s) that ordered a Gas Range and Washer]
FROM CUSTOMER C
INNER JOIN ORDERS O
ON C.CUST_NUM = O.CUST_NUM
INNER JOIN ORDER_LINE OL
ON O.ORDER_NUM = OL.ORDER_NUM
INNER JOIN PART P
ON OL.PART_NUM = P.PART_NUM
INNER JOIN ORDERS O2
ON C.CUST_NUM = O2.CUST_NUM
INNER JOIN ORDER_LINE OL2
ON O2.ORDER_NUM = OL2.ORDER_NUM
INNER JOIN PART P2
ON OL2.PART_NUM = P2.PART_NUM
WHERE P.PART_DESCRIPTION IN ('GasRange') and P2.PART_DESCRIPTION IN ('Washer')
GROUP BY C.CUST_NAME
EDIT: Had a further look and I'm afraid that this can't be simplified in any other way than using WITH and complicated aggregate functions, which I would say would be more complicated than this - I think the other solution suggested using WITH won't work - it joins incorrectly. You definitely can't remove order line, and you have to use the order twice as well - if it was used once, it will cover only when the customer ordered it within one order, which is not what you wanted ;)
Try this...
So basically you need to join your Parts table again to ensure the same customer ordered a "Gas Range" and a "Washer". An IN, like in your current query functions as an OR therefore you are not getting the expected result.
WITH CTE AS (
SELECT DISTINCT O.CUST_NUM FROM ORDERS O
INNER JOIN ORDER_LINE OL
ON O.ORDER_NUM = OL.ORDER_NUM
INNER JOIN PART P
ON OL.PART_NUM = P.PART_NUM
INNER JOIN PART P2
ON OL.PART_NUM = P2.PART_NUM
WHERE P.PART_DESCRIPTION IN ('GasRange')
AND P2.PART_DESCRIPTION IN ('Washer')
)
SELECT C.CUST_NAME AS [Customer(s) that ordered a Gas Range and Washer]
FROM CUSTOMER C
INNER JOIN CTE O
ON C.CUST_NUM = O.CUST_NUM