mysql - php . How to find
i have 2 table
users : id , name
order : id , price, user_id
a users have more than one order. And i want to select a users
who have total price >100 . how to do ?
EX : user John have 3 orders with pri开发者_运维技巧ce : 30$, 40$ , 50$
SELECT * FROM user u
INNER JOIN order o ON o.user_id = u.id
WHERE sum(o.price) >100
this query will get the user is john ? 30+40+50 = 110 >100 ?
First of all you are not allowed to use aggregate functions (i.e. SUM
) in your WHERE
clause. They should be used in the HAVING
clause. To compute aggregates you need to GROUP BY
something, in your case by u.id
.
So:
SELECT *
FROM user u
INNER JOIN order o ON u.user_id = u.id
GROUP BY u.id
HAVING sum(o.price) > 100
Note that if you would need users with no order you would have to use LEFT JOIN
!
SELECT u.Id, Sum(o.price) FROM user u
INNER JOIN order o ON o.user_id = u.id
GROUP BY u.Id
HAVING sum(o.price) > 100
Thank for all answer but i catch problem now i have a new table order_file
users : id , name
order : id , price, user_id
order_file : id , file , order_id
users, order is one-many
order , order_file is one-many
a user John have 1 order with price is 200$ and this order link to order_file with two record
SELECT *
FROM user u
INNER JOIN order o ON u.user_id = u.id
INNER JOIN order_file of ON of.order_id = o.id
WHERE u.name = 'John'
we will get two rows.Only diff value in order_file
now to get once i use DISTINCT , and i get 1 row
SELECT DISTINCT *
FROM user u
INNER JOIN order o ON u.user_id = u.id
INNER JOIN order_file of ON of.order_id = o.id
WHERE u.name = 'John'
then i do SUM , oh la la , i get 400$ , not 200$
SELECT DISTINCT *, sum(o.price)
FROM user u
INNER JOIN order o ON u.user_id = u.id
INNER JOIN order_file of ON of.order_id = o.id
WHERE u.name = 'John'
how to i can get extracty 200$ , not duplicate row :(
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