Is there a way to sum rows only when one of the columns has a certain value? I have this table:
| order_id | total | is_tip |
-----------------------------
| 1 | 12 | 1 |
| 1 | 3 | 0 |
| 2 | 28 | 0 |
| 2 | 15 | 0 |
| 3 | 39 | 1 |
| 3 | 8 | 1 |
The desired result would be:
| order_id | SUM(total) |
-------------------------
| 1 | 15 |
| 3 | 47 |
It would only sum up if one of the is_tip columns is equal to 1. So order IDs 1 and 3 are qualified. So far I've tried to use this query:
SELECT order_id, SUM(total) FROM orders HAVING COUNT(is_tip) >= 1;
But this query is so wrong. I'm just a beginner. Thank you in advance.
Use a having clause:
SELECT order_id, SUM(total)
FROM orders
GROUP BY order_id
HAVING SUM(is_tip) >= 1;
Your query also needs a GROUP BY. And I'm assuming you want a row with at least one "tip". You can also phrase the HAVING clause as:
HAVING MAX(is_tip) > 0
Please use below query,
SELECT order_id, SUM(total) FROM orders where is_tip >= 1 group by order_id;
Having can be used only where you want to filter on aggregation basis
Related
I have created a SQLfiddle demo with sample data and desired result here :(http://sqlfiddle.com/#!9/dfe73a/7)
sample data
-- table company
+--------+---------+
| id | name |
+--------+---------+
| 1 | foo |
| 2 | bar |
+--------+---------+
-- table sales
+--------+---------------+-----------------+
| id | company_id | total_amount |
+--------+---------------+-----------------+
| 1 | 1 | 300.0 |
| 2 | 1 | 300.0 |
| 2 | 1 | 100.0 |
+--------+---------------+-----------------+
-- table moves
+--------+---------------+-----------------+
| id | company_id | balance_move |
+--------+---------------+-----------------+
| 1 | 1 | 700.0 |
| 2 | 1 | -300.0 |
| 2 | 1 | -300.0 |
+--------+---------------+-----------------+
I need to select every company along with the sum of it's total amount of sales and the sum of it's total balance moves
desired result
+----+----------------------+---------------------+
| id | total_amount_sum | balance_move_sum |
+----+----------------------+---------------------+
| 1 | 700 | 100 |
+----+----------------------+---------------------+
| 2 | (null) | (null) |
+----+----------------------+---------------------+
I tried this SQL query
SELECT
company.id,
sum(total_amount) total_amount_sum,
sum(balance_move) balance_move_sum
FROM company
LEFT JOIN sales ON company.id = sales.company_id
LEFT JOIN moves ON company.id = moves.company_id
GROUP BY company.id
But the sum() functions add all the redundant values came from the joins which result in 2100 (700*3) for total amount and 300 (100*3) for net balance
bad SQL statement result
+----+----------------------+---------------------+
| id | total_amount_sum | balance_move_sum |
+----+----------------------+---------------------+
| 1 | 2100 | 300 |
+----+----------------------+---------------------+
| 2 | (null) | (null) |
+----+----------------------+---------------------+
Is it possible to achieve the result I want ?
You're repeating rows by doing your joins.
Company: 1 row per company
After Sales join: 3 rows per company (1x3)
After Moves join: 9 rows per company (3x3)
You end up triplicating your SUM because of this.
One way to fix is to use derived tables like this, which calculate the SUM first, then join the resulting rows 1-to-1.
SELECT
company.id,
total_amount_sum,
balance_move_sum
FROM company
LEFT JOIN (SELECT SUM(total_amount) total_amount_sum, company_id
FROM sales
GROUP BY company_id
) sales ON company.id = sales.company_id
LEFT JOIN (SELECT SUM(balance_move) balance_move_sum, company_id
FROM moves
GROUP BY company_id
) moves ON company.id = moves.company_id
Using sub-queries to calculate the two sums separately will work.
SELECT
company.id,
(Select sum(total_amount) from sales where sales.company_id = company.id) total_amount_sum,
(Select sum(balance_move) from moves where moves.company_id = company.id) balance_move_sum
FROM company
I have a table (Table1) with the columns order_item_id customer_id and order_id in which I want to count the number of orders per customer. Unfortunately an order with more than one article has the same order_id
|order_item_id|order_id|customer_id|
| 2 | 30 | 1 |
| 3 | 30 | 1 |
| 4 | 42 | 1 |
| 5 | 33 | 2 |
| 11 | 32 | 3 |
| 12 | 33 | 2 |
| 13 | 33 | 2 |
| 19 | 69 | 3 |
Expected Outcome:
|numberOfOrders|customer_id|
| 2 | 1 |
| 1 | 2 |
| 2 | 3 |
I tried this (and many more):
CREATE TABLE X AS
SELECT
customer_id,
COUNT(order_id) AS `numberOfOrders`
FROM Table1 T1
GROUP BY customer_id;
The problem is, that with this solution it counts every article not the number of orders: so the number of orders for customer 1 is 3 (not 2), for customer 2 is 3 (not 1)....
How can I solve this for a big database with Mysql query?
Try the following solution to SELECT your data as expected:
SELECT COUNT(DISTINCT order_id) AS numberOfOrders, customer_id
FROM table1
GROUP BY customer_id
Demo: http://sqlfiddle.com/#!9/ee8f62/1/0
An option could be to do GROUP twice. First GROUP for the number of items per order, wrapped by a second GROUP for the number of orders per customer:
/* second group */
SELECT customer_id
, count(*) AS number_of_orders
FROM (
/* first group */
SELECT order_id
, customer_id
, count(*) AS order_item_count
FROM Table1
GROUP BY order_id, customer_id
) a
GROUP BY customer_id
I have the following table:
+---------+--------------+----------+
| item_id | location_id | price |
+---------+--------------+----------+
| 1 | 1 | 100 |
| 1 | 1 | 250 |
| 1 | 2 | 50 |
| 2 | 1 | 250 |
| 2 | 1 | 1000 |
| 3 | 1 | 1000 |
| 3 | 2 | 100 |
+---------+--------------+----------+
I can reduce this down to the minimum values using this query
SELECT
item_id, location_id, MIN(price) AS Price
from
table
GROUP BY item_id , location_id
This gets me
+---------+--------------+----------+
| item_id | location_id | price |
+---------+--------------+----------+
| 1 | 1 | 100 |
| 1 | 2 | 50 |
| 2 | 1 | 250 |
| 3 | 1 | 1000 |
| 3 | 2 | 100 |
+---------+--------------+----------+
I want to reduce this further. I am using the rows with a location_id of 1 as a reference row. For each row that has an item_id matching the reference row's item_id but a different location id. I want to compare that row's price with the reference row's price. If the price is lower than the reference row's price, I want to filter that row out.
My final result should include the reference row for each item id and any rows that met the criteria of the price being lower than the reference row price.
I have a hunch that I can use the HAVING clause to do this but I am having trouble compiling the statement. How should I construct the HAVING statement?
Thanks in advance
Nah, having can't help you like this, having is for things like you need filter min() result for something
e.g:
select id,min(price) from table where date = '2016-3-18' group by id having min(price) = 50
it will show you the records that min(price)=50
let's back to your case, there are lots of way to do that,
1. left join
select a.item_id,a.location_id,a.price
from table a
left join table b
on a.location_id = b.location_id and a.price > b.price
where b.price is null
2. exists
select a.item_id,a.location_id,a.price
from table a
where exists(
select 1 from
(select location_id,min(price)as price from table group by location_id)b
where a.location_id = b.location_id and a.price = b.price
)
normally i ll recommand you use exists
I have two tables, one that store product information and one that stores reviews for the products.
I am now trying to get the number of reviews submitted for the products between two dates but for some reason I get the same results regardless of the dates i put.
This is my query:
SELECT
productName,
COUNT(*) as `count`,
avg(rating) as `rating`
FROM `Reviews`
LEFT JOIN `Products` using(`productID`)
WHERE `date` BETWEEN '2015-07-20' AND '2015-07-30'
GROUP BY
`productName`
ORDER BY `count` DESC, `rating` DESC;
This returns:
+------------+---------------------+
| productName| count|rating |
+------------+------+--------------+
| productA | 23 | 4.3333333 |
| productB | 17 | 4.25 |
| productC | 10 | 3.5 |
+------------+---------------------+
Products table:
+---------+-------------+
|productID | productName|
+---------+-------------+
| 1 | productA |
| 2 | productB |
| 3 | productC |
+---------+-------------+
Reviews table
+---------+-----------+--------+---------------------+
|reviewID | productID | rating | date |
+---------+-----------+--------+---------------------+
| 1 | 1 | 4.5 | 2015-07-27 17:47:01|
| 2 | 1 | 3.5 | 2015-07-27 18:54:22|
| 3 | 3 | 2 | 2015-07-28 13:28:37|
| 4 | 1 | 5 | 2015-07-28 18:33:14|
| 5 | 2 | 1.5 | 2015-07-29 11:58:17|
| 6 | 2 | 3.5 | 2015-07-30 15:04:25|
| 7 | 2 | 2.5 | 2015-07-30 18:11:11|
| 8 | 1 | 3 | 2015-07-30 18:26:23|
| 9 | 1 | 3 | 2015-07-30 21:35:05|
| 10 | 1 | 4.5 | 2015-07-31 14:25:47|
| 11 | 3 | 0.5 | 2015-07-31 14:47:48|
+---------+-----------+--------+---------------------+
when I put two random dates that I do know for sure they not on the date column, I will still get the same results. Even when I want to retrieve records only on a certain day, I get the same results.
You should not use left join, because by doing so you retrieve all the data from one table. What you should use is something like :
select
productName,
count(*) as `count`,
avg(rating) as `rating`
from
products p,
reviews r
where
p.productID = r.productID
and `date` between '2015-07-20' and '2015-07-30'
group by productName
order by count desc, rating desc;
If the result, given your sample data, that you're looking for is:
| productName | count | rating |
|-------------|-------|--------|
| productA | 5 | 4 |
| productB | 3 | 3 |
| productC | 1 | 2 |
This is the count and average of reviews made on any date between 2015-07-20 and 2015-07-30 inclusive.
Then the there are two issues with your query. First, you need to change the join to a inner join instead of a left join, but more importantly you need to change the date condition as you are currently excluding reviews that fall on the last date on the range, but after midnight.
This happens because your between clause compares datetime values with date values so the comparison ends up being date between '2015-07-20 00:00:00' and '2015-07-30 00:00:00' which clearly excludes some dates at the end.
The fix is to either change the date condition so that the end is a day later:
where date >= '2015-07-20' and date < '2015-07-31'
or cast the date column to a date value, which will remove the time part:
where date(date) between '2015-07-20' and '2015-07-30'
Sample SQL Fiddle
You are using a LEFT JOIN between your reviews and your products tables. This will result in all the rows of reviews being shown with some rows having all product columns left empty.
You should use INNER JOIN, as this will filter only the wanted results.
(In the end I can only guess, since I don't even know which column belongs to which table ...)
The full query (very similar to Angelo Giannis's solution):
select
productName,
count(*) as `count`,
avg(rating) as `rating`
from
products INNER JOIN reviews USING(productId)
where date between '2015-07-20' and '2015-07-30'
group by productName
order by count desc, rating desc;
Here a fiddle with my and Angelo's solution (they both work).
I'm trying to do something like 'select groupwise maximum', but I'm looking for groupwise order number.
so with a table like this
briefs
----------
id_brief | id_case | date
1 | 1 | 06/07/2010
2 | 1 | 04/07/2010
3 | 1 | 03/07/2010
4 | 2 | 18/05/2010
5 | 2 | 17/05/2010
6 | 2 | 19/05/2010
I want a result like this
breifs result
----------
id_brief | id_case | dateOrder
1 | 1 | 3
2 | 1 | 2
3 | 1 | 1
4 | 2 | 2
5 | 2 | 1
6 | 2 | 3
I think I want to do something like described here MySQL - Get row number on select, but I don't know how I would reset the variable for each id_case.
This will give you how many records are there with this id_case value and a date less than or equal to this date value.
SELECT t1.id_brief,
t1.id_case,
COUNT(t2.*) AS dateOrder
FROM yourtable AS t1
LEFT JOIN yourtable AS t2 ON t2.id_case = t1.id_case AND t2.date <= t1.date
GROUP BY t1.id_brief
Mysql is permissive about columns which can be queries using GROUP BY. With a more stric DBMS you may need GROUP BY t1.id_brief, t1.id_case.
I strongly advise you to have the right indexes on the table:
CREATE INDEX filter1 ON yourtabl (id_case, date)