How can I select latest records in a a table with many-to-many relationship. The store_id,product_id is not a composite group key so they repeat many times.
id store_id product_id
1 1 1
2 2 1
3 1 1
4 3 1
5 2 1
6 3 1
The result should be like this:
id store_id product_id
3 1 1
5 2 1
6 3 1
For the sake of simplicity I only added 1 product but in the real case there are many products. So the result should be something like :
For each store_id show the latest added products_id.
e.g.
id store_id product_id
11 1 1
20 1 2
40 1 3
41 1 4
53 2 1
61 2 2
62 2 3
63 2 4
70 3 1
71 3 2
72 3 3
73 3 4
I don't see what this has to do with a pivot table. This seems like a basic aggregation:
select max(id) as id, store_id, product_id
from t
group by store_id, product_id
order by store_id, max(id);
Related
Hi Experts I have a table like this
T1
Order_no
Qty
1
3
2
5
3
1
4
3
I need to generate a column 'serial no' having values based on 'qty'
Output needed
OrderNo
Qty
SerailNo
1
3
1
1
3
2
1
3
3
2
5
1
2
5
2
2
5
3
2
5
4
2
5
5
3
1
1
4
3
1
4
3
2
4
3
3
Any suggestions?
Thanks in advance!!
You don't mention the specific database so I'll assume you are using PostgreSQL, aren't you?
You can use a Recursive CTE to expand the rows. For example:
with recursive
n as (
select order_no, qty, 1 as serial_no from t1
union all
select order_no, qty, serial_no + 1
from n
where serial_no < qty
)
select * from n order by order_no, serial_no
Result:
order_no qty serial_no
--------- ---- ---------
1 3 1
1 3 2
1 3 3
2 5 1
2 5 2
2 5 3
2 5 4
2 5 5
3 1 1
4 3 1
4 3 2
4 3 3
See running example at DB Fiddle.
EDIT FOR ORACLE
If you are using Oracle the query changes a bit to:
with
n (order_no, qty, serial_no) as (
select order_no, qty, 1 from t1
union all
select order_no, qty, serial_no + 1
from n
where serial_no < qty
)
select * from n order by order_no, serial_no
Result:
ORDER_NO QTY SERIAL_NO
--------- ---- ---------
1 3 1
1 3 2
1 3 3
2 5 1
2 5 2
2 5 3
2 5 4
2 5 5
3 1 1
4 3 1
4 3 2
4 3 3
See running example at db<>fiddle.
You should first provide the database you're using. Whether it's oracle, Sql Server, PostGreSQL will determine which procedural language to use. It's very likely that you'll need to do this in two steps:
1st: Duplicate the number of rows based on the column Qty using a decreasing loop
2nd: You'll need to create a sequential partionned column based on the Qty column
1.I have data as follows (just a subset - there are 20K records)
sku,id
1 1
1 2
1 2
1 2
1 3
1 4
1 1
1 2
1 3
1 4
1 4
1 4
1 5
1 6
1 6
2 1
2 1
2 2
2 3
2 3
2 3
2 4
2 4
2 5
2 5
2 6
2 7
2 1
2 2
2 3
The above values translate to
1 = 4 records
1 = 6 records
2 = 7 records
2 = 3 records
The MAX would just give me 6 for one and 7 for 2
The actual total is 1 = 10 and 2 = 10
How do I sum up to get the correct values?
You can use order by and some way of limiting rows. In standard SQL this would be:
select t.*
from t
order by id desc
fetch first 2 rows only;
However, some databases might use limit or select top or some other method.
No handling of ties here. Thousands of other questions handle this topic.
select sku, id
from (
select *, row_number() over (order by id desc) rn
from T
) t
where rn <= 2
order by rn desc;
I need to make a query over an SQL Server table but I don't know exactly how.
Consider this table (the real table is much more complex, Ord1 and Ord2 are dates that could be null, but i simplified it to this case):
Data of MyTable
ID MaqID Ord1 Ord2
------------------------
1 144 4 3
2 144 2 1
3 12 2 3
4 144 3 5
5 12 3 1
6 144 4 2
7 12 2 4
8 144 2 3
9 12 1 5
10 12 3 2
I need records for specific MaqID in Specific Order. I get that with this Query:
SELECT * FROM myTable WHERE MaqID=144 ORDER BY MaqID, Order1 DESC, Order2
Wich give me:
ID MaqID Ord1 Ord2
------------------------
6 144 4 2
1 144 4 3
4 144 3 5
2 144 2 1
8 144 2 3
Now, I need a single query that, for each MaqID, return the first ID for each subquery following above order. The result should be:
Expected result
MaqID ID
-----------
144 6
12 5
I have already try distinct conbination of TOP a MAX, but TOP result only one result and i need one for each MaqID, and for Max I have not field to maximize.
To sumarize: I need the first ID for each MaqID from a subquery in a specific order
Any ideas? Thanks!
You can do this using row_number():
select t.*
from (select t.*,
row_number() over (partition by macid Order1 DESC, Order2) as seqnum
from mytable t
) t
where seqnum = 1;
I have a table which rank the items which i have.
I need a queries which will pick up only the top 2 ranks for a given item, the rank may not be in sequential order.
I need to fetch the item with least two ranks, there will same rank for two items as well.
Here is the snap shot of my table.
Item Id Supp Id Rank
1 2 2
1 1 7
1 7 5
1 9 11
2 67 4
2 9 14
2 10 14
2 34 4
2 25 3
2 60 3
2 79 5
my requirement is if I enter 2 i should get the result as below
Item Id Supp_id Rank
2 25 3
2 60 3
2 67 4
2 34 4
I am using oracle 10g version.
As one of the approaches it can be done as follows. Here we are using dense_rank() over() analytic function to assign a rank for a row in a ordered by rank group of rows .
select t.item_id
, t.supp_id
, t.rank
from (select item_id
, supp_id
, rank
, dense_rank() over(partition by item_id
order by rank) as rn
from t1
where item_id = 2
) t
where t.rn <= 2
Result:
ITEM_ID SUPP_ID RANK
---------- ---------- ----------
2 25 3
2 60 3
2 67 4
2 34 4
SQLFiddle Demo
I have this table structure
Product
product_id (PK)
name
Order_Detail
order_detail_id
product_id
quantity
Example data
Product :
1 product1
2 product2
3 product3
4 product4
5 product5
Order_Detail :
1 3 2
2 3 1
3 3 1
4 2 1
5 2 1
6 1 1
7 4 1
8 5 1
9 1 1
10 2 1
11 3 1
Please help me to get top 3 ordered product based on how many times the product ordered ?
I think this migth work:
SELECT p.`product_id`, p.`name`, SUM(o.`quantity`) AS quantity
FROM `Order_Detail` AS o
INNER JOIN `Product` AS p
ON o.`product_id` = p.`product_id`
GROUP BY o.`product_id`
ORDER BY SUM(o.`quantity`) DESC, p.`name` ASC
LIMIT 3