I am not sure if a similar question has been posted. I was unable to find one.
I have the following table:
What I trying to get is the below:
Any advice will be appreciated.
Thanks in advance,
Sam
Worked both in Oracle and Snowflake:
SELECT t.ID,
t.prev_dt,
t.current_dt,
t.prev_code,
t.curr_code
FROM (
SELECT id,
order_dt,
LAG(order_dt, 1) OVER (PARTITION by id ORDER BY id, order_dt) prev_dt,
upd_dt current_dt,
LAG(code, 1) OVER (PARTITION by id ORDER BY id, upd_dt) prev_code,
code curr_code
FROM t111
) t
INNER JOIN (
SELECT id,
MAX(order_dt) max_date
FROM t111
GROUP BY id
) idm
ON idm.id=t.id AND t.order_dt=idm.max_date
You seem to want window function lag():
select
id,
lag(order_dt) over(partition by id order by order_by_id) prev_dt,
order_dt current_dt,
lag(code) over(partition by id order by order_by_id) prev_code,
code curr_code
from mytable
Note that the above query does not filter the records of the table. When there is no preceeding record, lag() returns null. If you want to filter out the first record per group, and assuming that such record is identify by order_by_id = 1, you can do:
select *
from (
select
id,
lag(order_dt) over(partition by id order by order_by_id) prev_dt,
order_dt current_dt,
lag(code) over(partition by id order by order_by_id) prev_code,
code curr_code,
order_by_id
from mytable
) t
where order_by_id > 1
Window functions might be the best approach. But you could also use join:
select t1.id, t1.order_dt as prev_dt, t2.upd_dt as curr_date,
t1.code as prev_code, t2.code as curr_code
from t t1 join
t t2
on t1.id = t2.id and t1.order_by_id = 1 and t2.order_by_id = 2;
In Snowflake, I simply do not know whether this would have better, worse, or similar performance to using window functions.
Related
I need to select the data of all my customers with the records displayed in the image. But I need to get the most recent record only, for example I need to get the order # E987 for John and E888 for Adam. As you can see from the example, when I do the select statement, I get all the order records.
You don't mention the specific database, so I'll answer with a generic solution.
You can do:
select *
from (
select t.*,
row_number() over(partition by name order by order_date desc) as rn
from t
) x
where rn = 1
You can use analytical function row_number.
Select * from
(Select t.*,
Row_number() over (partition by customer_id order by order_date desc) as rn
From your_table t) t
Where rn = 1
Or you can use not exists as follows:
Select *
From yoir_table t
Where not exists
(Select 1 from your_table tt
Where t.customer_id = tt.custome_id
And tt.order_date > t.order_date)
You can do it with a subquery that finds the last order date.
SELECT t.*
FROM yoir_table t
JOIN (SELECT tt.custome_id,
MAX(tt.order_date) MaxOrderDate
FROM yoir_table tt
GROUP BY tt.custome_id) AS tt
ON t.custome_id = tt.custome_id
AND t.order_date = tt.MaxOrderDate
I have the following table:
I want to get the most recent status for each dept_code that a CL_ID has. So the desired output would be this:
I have tried the following but this give me just the most recent status for each client and not each of their dept_codes.
SELECT *
FROM [CIMSHR6_MERGED].[dbo].[C3CLSTAT] C
INNER JOIN
(SELECT CLIENT_NUMBER, MAX(STATUS_DATE) AS SDATE
FROM [CIMSHR6_MERGED].[dbo].[C3CLSTAT]
GROUP BY CLIENT_NUMBER) X
ON X.CLIENT_NUMBER = C.CLIENT_NUMBER
AND X.SDATE = C.STATUS_DATE
ORDER BY C.CLIENT_NUMBER
Any help would be much appreciated. Thanks.
A convenient method that works in SQL Server is:
select top (1) cl.*
from [CIMSHR6_MERGED].[dbo].[C3CLSTAT] cl
order by row_number() over (partition by cl_id, dept_code order by status_date desc);
A method that is efficient with the right indexes in almost any database is:
select cl.*
from [CIMSHR6_MERGED].[dbo].[C3CLSTAT] cl
where cl.status_date = (select max(cl2.status_date)
from [CIMSHR6_MERGED].[dbo].[C3CLSTAT] cl2
where cl2.cl_id = cl.cl_id and cl2.dept_code = cl.dept_code
);
The right index is on (cl_id, dept_code, status_date).
I would also use ROW_NUMBER, but with a subquery:
SELECT CL_ID, Status_date, Status, Dept_code
FROM
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY CL_ID, Dept_code ORDER BY Status_date DESC) rn
FROM CIMSHR6_MERGED].[dbo].[C3CLSTAT]
) t
WHERE rn = 1;
1) Firstly group everything on Dept_Code,CL_ID and assign rank for each row with in the group in descending order.
2) Select all the rows with rnk=1 which would display your desired result.
SELECT Z.CL_ID,
Z.Status_Date,
Z.Status,
Z.Dept_Code
FROM
(
SELECT *,
RANK() OVER( PARTITION BY Dept_Code,CL_ID, ORDER BY Status_Date DESC ) AS rnk
FROM [CIMSHR6_MERGED].[dbo].[C3CLSTAT]
) Z
WHERE Z.rnk = 1;
This would work for almost all databases
select * from c3clstat c
where exists
(select 1 from c3clstat c1
where c1.cl_id=c.cl_id
and c1.dept_code=c.dept_code
group by cl_id,dept_code
having c.status_date=max(c1.status_date)
)
So I have a table that looks something like this:
Now, I want the max totalcst for both days, something like this:
I tried using different variations of max and the Row_number funtion but still can't seem to get the result I want. My query:
select date,pid,max(quan*cst), totalcst
from dbo.test1
group by date, pid
But this returns all the records. So if somebody can point me towards the right direction, that would be very helpful.
Thanks in advance!
ROW_NUMBER should work just fine:
WITH CTE AS
(
SELECT *,
RN = ROW_NUMBER() OVER(PARTITION BY [date] ORDER BY totalcst)
FROM dbo.YourTable
)
SELECT [date],
pid,
totalcst
FROM CTE
WHERE RN = 1
;
Here is one simple way:
select t.*
from test1 t
where t.totalcst = (select max(t2.totalcst) from test1 t2 where t2.date = t.date);
This often has the best performance if you have an index on (date, totalcst). Of course, row_number()/rank() is also a very acceptable solution:
select t.*
from (select t.*, row_number() over (partition by date order by totalcst desc) as seqnum
from test1
) t
where seqnum = 1;
I have this query:
SELECT * FROM TABLE1 WHERE KEY_COLUMN='NJCRF' AND TYPE_COLUMN IN ('SCORE1', 'SCORE2', 'SCORE3') AND DATE_EFFECTIVE_COLUMN<='2016-09-17'
I get about 12 record(rows) as result.
How to get result closest to DATE_EFFECTIVE_COLUMN for each TYPE_COLUMN? In this case, how to get three records, for each type, that are closest to effective date?
UPDATE: I could use TOP if I had to go over only single type, but I have three at this moment and for each of them I need to get closest time result.
Hope I made it clear, let me know if you need more info.
If I understand correctly, you can use ROW_NUMBER():
SELECT t.*
FROM (SELECT t.*,
ROW_NUMBER() OVER (PARTITION BY TYPE_COLUMN ORDER BY DATE_EFFECTIVE_COLUMN DESC) as seqnum
FROM TABLE1 t
WHERE KEY_COLUMN = 'NJCRF' AND
TYPE_COLUMN IN ('SCORE1', 'SCORE2', 'SCORE3') AND
DATE_EFFECTIVE_COLUMN <= '2016-09-17'
) t
WHERE seqnum = 1;
If you want three records per type, just use seqnum <= 3.
I like ROW_NUMBER() for this. You want to partition by TYPE, which will start the row count over for each type, then order by DATE_EFFECTIVE desc, and take only the highest date (the first row):
SELECT *
FROM (
SELECT *,
ROW_NUMBER() over (PARTITION BY TYPE_COLUMN ORDER BY DATE_EFFECTIVE_COLUMN desc) RN
FROM TABLE1
WHERE KEY_COLUMN = 'NJCRF'
AND TYPE_COLUMN IN ('SCORE1', 'SCORE2', 'SCORE3')
AND DATE_EFFECTIVE_COLUMN <= '2016-09-17'
) A
WHERE RN = 1
How to fetch records with latest 2 version numbers from a table using SQL query.
I want to fetch user ids for a tracking id for the last 2 versions.
Below is my table description:
TRACKING_ID ,
User_id,
Version_number
Below query gives me the user id having the latest version.
Select user_id
from table t1
join
(select tracking_id,max(version_number) as version_number
from table
group by tracking_id ) t2
on t1.tracking_id=t2.tracking_id
and t1.version_number=t2.version_number
Appreciate your response.
You can use ROW_NUMBER:
SELECT tracking_id,
user_id,
version_number
FROM ( SELECT *,
ROW_NUMBER() OVER(PARTITION BY tracking_id ORDER BY version_number DESC) AS RN
FROM YourTable) AS T
WHERE RN <= 2
I don't fully understand the question but something like this may point you in the correct direction.
WITH CTE AS (
SELECT tracking_ID, user_ID, version_number,
Row_number() over (partition by USER_ID, Version_number desc) as RN)
SELECT *
FROM cte
WHERE RN <= 2;
I'm not sure if the user_ID or the tracking_ID needs to be partitioned...