I need to show data max from specified colum, is this even possible?
I am still newbie on this SQL.
I have data like this
Id Order_id Sequence
------------------------
1 A01 1
2 A01 2
3 A02 1
4 A02 2
5 A02 3
6 A03 1
Id is the primary key.
Expected result
Id Order_id Sequence
------------------------
2 A01 2
5 A02 3
6 A03 1
You need to do a sub-query:
SELECT t.id, t.order_id, t.sequence
FROM t
INNER JOIN
(SELECT order_id, MAX(sequence) as mx
FROM t
GROUP BY order_id) sub
ON t.order_id = sub.order_id
WHERE t.sequence = sub.mx
So basically the query called sub finds the max sequence value for each order ID. Then these results are joined back the main table, which I'm calling t, so you can slap on the id.
Use GROUP BY and ORDER BY
SELECT Id,Order_id,MAX(Sequence) AS Sequence FROM table_name GROUP BY Order_id ORDER BY Id
If you don't need the id in the result, you can just do a group by... otherwise you need an inner query as the answer provided by #kbball.
select order_id, max(sequence)
from tablename
Group by order_id;
You can use correlated subquery as below.
SELECT *
FROM table1 t1
WHERE t1.Sequence =
( SELECT max(t2.Sequence)
FROM table1 t2
WHERE t1.Order_id = t2.Order_id );
Result:
Id Order_id Sequence
------------------------
2 A01 2
5 A02 3
6 A03 1
DEMO
Related
I have a table with 100 000 record, I want to select only the none repeated.
In another word, if the row are duplicated did not show it at all
ID Name Reslut
1 Adam 10
2 Mark 10
3 Mark 10
result
ID Name Reslut
1 Adam 10
any ideas ?
You could join a query on the table with a query that groups by the name only returns the unique names:
SELECT *
FROM mytable t
JOIN (SELECT name
FROM mytable
GROUP BY name
HAVING COUNT(*) = 1) s ON t.name = s.name
Using the same set :
ID Name Result
1 Adam 10
2 Mark 10
3 Mark 10
4 Mark 20
I'm guessing the final solution would be:
ID Name Result
1 Adam 10
4 Mark 20
Using the above query previously suggested I modified it to take the result into consideration:
SELECT t1.*
FROM myTable t1
JOIN
(
SELECT name, result
FROM myTable
GROUP BY name, result
HAVING COUNT(*) = 1
) t2
WHERE
t1.name=t2.name and
t1.result = t2.result;
I have a requirement :
ID Quantity
1 5
1 4
1 2
1 4
2 1
2 2
2 3
3 1
3 3
3 2
Output required :
ID Quantity
1 15
2 6
3 6
I have tried the below query on MySQL but unable to get appropriate result.
SELECT
a.id, sum(b.Quantity)
FROM
table_name a
INNER JOIN
table_name b
ON a.id = b.id
group by
a.id, b.Quantity
Just remove b.Quantity from group by statement. SQL fiddle
SELECT
a.id, sum(b.Quantity)
FROM
table_name a
INNER JOIN
table_name b
ON a.id = b.id
group by
a.id
http://sqlfiddle.com/#!9/003625/1
SELECT id, SUM(quantity)
FROM `table_name`
GROUP BY id
You don't need any join. Simply try:
select id,sum(quantity) from table_name group by id
Use GROUP BY clause along with sum() like the query below-
select ID, sum(Quantity) FROM table_name GROUP BY ID;
I'm running a query that selects details of orders, and I want to see only the orders that have gone through multiple stages. My data looks like:
id | order_id | action
1 100 1
2 100 2
3 100 4
4 101 1
5 102 2
6 103 1
7 103 2
So that only the rows for order_id 100 and 103 will be selected. This needs to be nested in a larger query.
You can use a subquery to get the orders that had multiple stages:
SELECT order_id
FROM your_table
GROUP BY order_id
HAVING COUNT(*)>1
then you can join this result back to your table:
SELECT o.*
FROM yourtable AS o INNER JOIN (
SELECT order_id
FROM your_table
GROUP BY order_id
HAVING COUNT(*)>1
) dup ON o.order_id = dup.order_id
Use group by with count and having
select *,count(order_id) as total from table
group by order_id
having total > 1
you can try this query:
select * from your_table
where ( select count(*) from your_table internal_table
where your_table .order_id = internal_table.order_id
) > 1
Hi there m trying to calculate the row count for same value,
id,value
1 | a
2 | b
3 | c
4 | d
5 | e
and my query is
select value, count(*) as Count from mytable where id in('4','2','4','1','4') group by value having count(*) > 1
for which my expected output will be,
value,Count
d | 3
b | 1
a | 1
Thanks, any help will be appreciated
Try that:
SELECT value, count(value) AS Count
FROM mytable m
WHERE value = m.value
GROUP BY value
SELECT t.id, t.value, COUNT(t.id)
FROM
test t
JOIN
( SELECT 1 AS id
UNION ALL SELECT 3
UNION ALL SELECT 3
UNION ALL SELECT 4
UNION ALL SELECT 1
UNION ALL SELECT 1 ) AS tmp
ON t.id = tmp.id
GROUP BY t.id
Sample on sqlfiddle.com
See also: Force MySQL to return duplicates from WHERE IN clause without using JOIN/UNION?
Of course, your IN parameter will be dynamic, and thus you will have to generate the corresponding SQL statement for the tmp table.
That's the SQL-only way to do it. Another possibility is to have the query like you have it in your question and afterwards programmatically associate the rows to the count passed to the IN parameter.
I am writing a query to grab the items that a specific user_id was the first to use. Here is some sample data -
item_id used_user_id date_used
1 1 2012-08-25
1 2 2012-08-26
1 3 2012-08-27
2 2 2012-08-27
3 1 2012-08-27
4 1 2012-08-21
4 3 2012-08-24
5 3 2012-08-23
query
select item_id as inner_item_id, ( select used_user_id
from test
where test.item_id = inner_item_id
order by date_used asc
limit 1 ) as first_to_use_it
from test
where used_user_id = 1
group by item_id
It returns the correct values
inner_item_id first_to_use_it
1 1
3 1
4 1
but the query is VERY slow on a giant table. Is there a certain index that I can use or a better query that I can write?
i can't get exactly what you mean because in your inner query you have sorted it by their used_user_id and and on your outer query you have filtered it also by their userid. Why not do this directly?
SELECT DISTINCT item_id AS inner_item_id,
used_user_id AS first_to_use_it
FROM test
WHERE used_user_id = 1
UPDATE 1
SELECT b.item_id,
b.used_user_id AS first_to_use_it
FROM
(
SELECT item_ID, MIN(date_used) minDate
FROM tableName
GROUP BY item_ID
) a
INNER JOIN tableName b
ON a.item_ID = b.item_ID AND
a.minDate = b.date_used
WHERE b.used_user_id = 1