I have a table containing customers and another containing all orders.
I want to display a list of customers and along side show the total value of their orders.
Obviously I could loop through the customers and then using PHP run another query to get each customer's revenue. I don't think this is efficient.
I am looking to achieve something like this:
SELECT username, [SELCT sum(revenue) from orders where userID=userID] from customers
And for this to show output:
bob 10000
jeff 25000
alan 500
SELECT a.username, SUM(b.revenue) totalRevenue
FROM customers a
LEFT JOIN Orders b
ON a.userID = b.UserID
GROUP BY a.username
This will list all customers with or without Orders.
To further learn more about join, please visit the article below,
Visual Representation of SQL Joins
you're close...
SELECT username, (SELECT sum(revenue) from orders where userID=c.userID) rev
from customers c
You can join the tables and the group them by the order name
SELECT o.username,
sum(revenue) as sum_revenue
from orders o
left outer join customers c on c.userid = o.userid
group by o.username
No need for a subselect with that. Try something like this:-
SELECT customers.userID, customers.username, SUM(revenue)
FROM customers INNER JOIN orders ON customers.userID = orders.userID
GROUP BY customers.userID, customers.username
Related
I have two MySQL-tables:
Persons (pid,name,companyID,companyName)
Orders (oid,companyID,details)
Now I want to count the number of order_id for each companyName as following:
Name Total
-------------------
CompanyName1 : 1200
CompanyName2 : 758
CompanyName3 : 11
I used this query but it's not working properly.
SELECT count(o.oid) as total,p.companyName
FROM orders as o, persons as p
WHERE o.companyID = p.companyID
GROUP BY p.companyName
Use join and group the result by p.companyID
SELECT p.companyName, count(o.oid) as total
FROM orders as o join persons as p
on o.companyID = p.companyID
GROUP BY p.companyID
If you are missing the companies without any orders you can use a left join.
SELECT p.companyName, count(*) as total
FROM persons p
LEFT JOIN orders o ON o.companyID = p.companyID
GROUP BY p.companyID, p.companyName
Please do not use the old, legacy join syntax any more - it is outdated since 1992.
Your data model looks messed up. That you have company ids and names in the person table but no corresponding companies table is highly suspicious.
In any case, presumably there can be multiple rows per company. You can condense the persons table and then join:
SELECT c.companyName, COUNT(*) as total
FROM orders o JOIN
(SELECT DISTINCT companyId, companyName
FROM persons p
) c
ON o.companyID = c.companyID
GROUP BY c.companyName;
However, you should fix the data model so you have a real bona fide companies table -- especially because you seem to care about that entity.
first sorry, i don't have fluid english.
I want select 3 rows in 3 different tables, two of them without Foreing Key/relation.
Need to select amount of customers in each store, and total amount of payments in these stores in one query.
Here are the tables:
Customers
Stores
Payments
I have tried these querys to get payments for each store and customers for each store, but don't know how can unify in one query:
Payments/store
SELECT count(a.payment_id) as alquileres, b.store_id
FROM customer b, payment a
WHERE a.customer_id = b.customer_id
GROUP BY b.store_id;
customers/store
SELECT count(customer_id), store_id
FROM customer
GROUP BY store_id;
But when I add count(customer_id) in unique query don't have same results.
You can use one query:
select c.store_id,
count(distinct c.customer_id) as num_customers,
count(p.payment_id) as num_payments
from customers c left join
payments p
on p.customer_id = c.customer_id
group by c.store_id;
i am having problems using an inner join for 3 tables..
i need to display cust_id, the customer forename and surname, the product name<-(from products table) and date of sale<--(from sales table), also i need to display in order of the most recent dates first.
this is what i have got so far
enter SELECT
customers.cust_id,
customers.forename,
customers.surname,
products.prod_name,
sales.Date_of_sale
FROM
customers
INNER JOIN
sales
ON
customers.cust_id = sales.cust_id; here
id really appreciate it if you could help me here, thank you..
Just add one more JOIN to the products table and include an ORDER BY clause:
SELECT
c.cust_id,
c.forename,
c.surname,
p.prod_name,
s.Date_of_sale
FROM customers c
INNER JOIN sales s ON c.cust_id = s.cust_id
INNER JOIN products p ON s.product_id = p.product_id
ORDER BY s.Date_of_sale DESC
A Visual Explanation of SQL Joins
I think the problem is in your FROM parameter.
You specified only customer.
SELECT customers.cust_id, customers.forename, customers.surname, products.prod_name, sales.Date_of_sale
FROM
customers , products , sales
INNER JOIN
sales
ON
customers.cust_id = sales.cust_id;
This is a part of SQL coding project of database.
I need to design a single table to hold orders made by customers.
Assume that customers' details (e.g. names) are stored in another table.
Using the table that I designed for orders, and this assumed other table, write
a single SQL query that can give the number of orders for every customer, one line per customer.
The “Orders” table
Order_ID Order_NO Customer_ID
1 8088 3
2 9632 1
3 1272 4
4 6037 1
Assume that the customer names and other details (address, phone numbers, emails) are stored in the “Customers” table.
My SQL:
SELECT Customers.FirstName, Customers.FirstName, Orders.OrderNo
FROM Customers
FULL JOIN Orders
ON Customers.Customer_ID = Orders.Customer_ID
ORDER BY Customers.LastName
Are there something wring with it ?
Change the query to inner join
SELECT
Customers.FirstName
, Customers.FirstName
, Orders.OrderNo
FROM
Customers
INNER JOIN Orders ON Customers.Customer_ID = Orders.Customer_ID
ORDER BY
Customers.LastName
Query for Ordercount for customer
SELECT
Customers.LastName
, COUNT(Orders.Order_Id)
FROM
Customers
INNER JOIN Orders ON Customers.Customer_ID = Orders.Customer_ID
GROUP BY
Customers.LastName
ORDER BY
Customers.LastName
Full join
http://www.w3schools.com/sql/sql_join_full.asp
Inner join
http://www.w3schools.com/sql/sql_join_inner.asp
If you just want to COUNT the orders you can do this:
SELECT
Customers.FirstName,
(
SELECT
COUNT(*)
FROM
Orders
WHERE
Orders.Customer_ID=Customers.Customer_ID
) AS NbrOfOrders
FROM
Customers
References:
12.15.1. GROUP BY (Aggregate) Functions
Don't forget COUNT and GROUP BY.
I have two tables that I am trying to join. One contains a list of customers, the other is a list of orders. I am trying to formulate a query that will allow me to select all of the customers listed in the table customers who have at least one order in the table orders. However, I do not want to get duplicates for those customers who have multiple orders. Any suggestions how I can accomplish this?
I know this is probably a common issue, however I have no idea what this type of query would be called so that I could search for an answer. Any suggestions would be greatly appreciated. Thanks.
It's much simpler than you may think:
select distinct(customer_id) from orders;
Edit: If you actually want to get the full info on the customer,
select * from customers where customer_id in (select distinct(customer_id) from orders);
Use:
SELECT c.*
FROM CUSTOMERS c
WHERE EXISTS (SELECT NULL
FROM ORDERS o
WHERE o.custeromid = c.id)
The IN clause is an alternative, but EXISTS works better for duplicates because it returns true on the first duplicate so it doesn't process the entire table.
select customers.id, customers.name, count(orders.id)
from customers
inner join orders on orders.customer_id = customers.Id
group by customers.id, customers.name
having count(orders.id) > 0
SELECT
c.id,
c.name
FROM
customer c
INNER JOIN order o ON o.customer_id = c.id
GROUP BY
c.id,
c.name
HAVING
COUNT(o.id) >= 1
Can't remember if HAVING or GROUP BY comes first.