Ranking Over Row_Number in SQL - sql

I am posting a sample data below.
What I have is a row number which generated a number based on Date and Name columns (achieved using ROW_NUMBER function). What I need now, is another derived column called Group_Num which creates a number for each group (3 in this case). Can this be achieved considering the fact that my Name column repeats but the Date column value changes?
Thanks in advance.

Check This.
We can achive this using Row_number() ,lag() and SUM() .
select
Date,
Name,
Row_number()over( partition by Group_Num order by ROwiD ) Row_Num,
Group_Num
from
(
SELECT * ,
SUM(R) OVER(ORDER BY RowID) Group_Num
FROM
(
select *,
Case When
lag(name ) OVER (ORDER BY RowID ) = name
then 0 else 1 end as R
from
(
select DATE,NAME,
row_number() OVER ( ORDER BY (select 1)) AS 'RowID'
from #TableName
)A
)B
)C
order by ROwiD
OutPut :

You can use DENSE_RANK:
SELECT Date
, Name
, ROW_NUMBER() OVER(Partition By Name Order By Name, Date) as Row_Num
, DENSE_RANK() Over(order by Name) as Group_Num
FROM #Table

Related

Max and Min row numbers from single cte code block

;with cte1 as
( select id,
row_number() over (partition by pk,pp,sn order by id asc)
as rn
from mqms_production
) select * into #M from cte1 where rn=1
With the above, I get all the rows with rn=1 but I also want to copy to another table all the rows with max rn for a given partition pk,pp, sn.
Is it possibleto do it without having to write the cte block again with
(partition by pk,pp,sn order by id DESC)
thanks!
You can just add another window function based expression there with reverse sort order and get the top rows on both of them
with cte1 as (
select id,
row_number() over (partition by pk,pp,sn order by id asc) as rn1,
row_number() over (partition by pk,pp,sn order by id desc) as rn2
from mqms_production
)
select * from cte1
where rn1 = 1 or rn2 = 1;

SQL Finding five largest numbers instead of one Max in a table

I have a table and I need to run a query that contains some aggregation Functions like Maximum , Average , Standard Deviation , ...
but instead of one Maximum I should return 5 largest number.
the simplified query is something like this:
SELECT OSI_KEY , MAX(VALUE) , AVG(VALUE) , STDDEV(VALUE), variance(VALUE)
FROM DATA_VALUES_5MIN_6_2013
GROUP BY OSI_KEY
ORDER BY OSI_KEY
and I need some Magical ;) Query like this:
SELECT OSI_KEY , MAX1(VALUE) ,MAX2(VALUE) ,MAX3(VALUE) ,MAX4(VALUE) , MAX5(VALUE) ,
AVG(VALUE) , STDDEV(VALUE), variance(VALUE)
FROM DATA_VALUES_5MIN_6_2013
GROUP BY OSI_KEY
ORDER BY OSI_KEY
I appreciate your considerations.
Oracle has an NTH_VALUE() function. Unfortunately, it is only an analytic function and not a window function. This leads to the strange construct of SELECT DISTINCT with a bunch of analytic functions:
SELECT DISTINCT OSI_KEY,
MAX(VALUE) OVER (PARTITION BY OSI_KEY),
NTH_VALUE(VALUE, 2) OVER (PARTITION BY OSI_KEY ORDER BY VALUE DESC) as MAX_2,
NTH_VALUE(VALUE, 3) OVER (PARTITION BY OSI_KEY ORDER BY VALUE DESC) as MAX_3,
NTH_VALUE(VALUE, 4) OVER (PARTITION BY OSI_KEY ORDER BY VALUE DESC) as MAX_4,
NTH_VALUE(VALUE, 5) OVER (PARTITION BY OSI_KEY ORDER BY VALUE DESC) as MAX_5,
AVG(VALUE) OVER (PARTITION BY OSI_KEY),
STDDEV(VALUE) OVER (PARTITION BY OSI_KEY),
variance(VALUE) OVER (PARTITION BY OSI_KEY)
FROM DATA_VALUES_5MIN_6_2013
ORDER BY OSI_KEY;
You can also do this using conditional aggregation, with a row_number() or dense_rank() in a subquery.
SELECT OSI_KEY, MaxValue FROM (
SELECT OSI_KEY, MAX(value) AS MaxValue FROM table GROUP BY OSI_KEY
)
ORDER BY MaxValue DESC
FETCH FIRST 5 ROWS ONLY;

SQL Server Partition Order - No tie DenseRank values even if rows are same

This question is best explained with an image and the script I have currently... How can I extract a FULL one row per assignment, with the lowest rank, and if there are 2 rows with a denserank as 1, then choose either of them?...
select *
,Dense_RANK() over (partition by [Assignment] order by [Text] desc) as
[DenseRank]
from [dbo].[CLEANSED_T3B_Step1_Res_Withdups____CP]
select * from
(
select *
,Dense_RANK() over (partition by [Assignment] order by [Text] desc, NewID()
) as [DenseRank] from [dbo].[CLEANSED_T3B_Step1_Res_Withdups____CP]
) as A
where A.[DenseRank] = 1
Second script is working perfectly!
SELECT * INTO
[dbo].[CLEANSED_T3B_Step1_COMPLETED]
from
(
select *
,Dense_RANK() over (partition by [Assignment] order by
left([Text],1) desc , [Diff_Doc_Clearing_Date] desc , [Amount] asc
as [DenseRank]
from [dbo].[CLEANSED_T3B_Step1_Res_Withdups____CP]
)
as A
where A.[DenseRank] = 1
No longer need just a random first Tied '1st place', now need to get the one with the highest day diff and then also the highest amount after. SO have adapted everything in this version 3.
It seems you don't want to use DENSE_RANK but ROW_NUMBER.
with cte as(
select t.*, rn = row_number() over(partition by assignment order by [text] desc)
from tablename t
)
select * from cte
where rn = 1
Order by 'newid()' as the 'tie-breaker'
Order by [Text],Newid()

How to select distinct records based on condition

I have table of duplicate records like
Now I want only one record from duplicate records which has latest created date as How can I do it ?
use row_number():
select EnquiryId, Name, . . .
from (select t.*,
row_number() over (partition by enquiryID order by CreatedDate desc) as seqnum
from table t
) t
where seqnum = 1;
Use ROW_NUMBER function to tag the duplicate records ordered by CreatedDate, like this:
;with CTE AS (
select *, row_NUMBER() over(
partition by EnquiryID -- add columns on which you want to identify duplicates
ORDER BY CreatedDate DESC) as rn
FROM TABLE
)
select * from CTE
where rn = 1

How to get the row that holds the last value in a queue of identical values? (SQL)

I think it's easier to show you an image:
So, for each fld_call_id, go to the next value, if it's identical. When we get to the last value, I need the value in column fld_menu_id.
Or, to put it in another way, eliminate fld_call_id duplicates and save only the last one.
You can use ROW_NUMBER:
WITH CTE AS(
SELECT RN = ROW_NUMBER() OVER (PARTITION BY fld_call_id ORDER BY fld_id DESC),
fld_menu_id
FROM dbo.TableName
)
SELECT fld_menu_id FROM CTE WHERE RN = 1
You can create a Rank column and only select that row, something along the lines of the following:
;WITH cte AS
(
SELECT
*
,RANK() OVER (PARTITION BY fld_call_id ORDER BY fld_id DESC) Rnk
FROM YourTable
)
SELECT
*
FROM cte
WHERE Rnk=1
So you GROUP BY fld_call_id and ORDER BY fld_id in descending order so that the last value comes first. These are the rows where Rnk=1.
Edit after comments of OP.
SELECT Table.*
FROM Table
INNER JOIN
(
SELECT MAX(fldMenuID) AS fldMenuID,
fldCallID
FROM Table
GROUP BY fldCallID
) maxValues
ON (maxValues.fldMenuID = Table.fldMenuID
AND maxValues.fldCallID= Table.fldCallID)
Hope This works
SELECT A.*
FROM table A
JOIN (SELECT fld_id,
ROW_NUMBER() OVER (PARTITION BY Fld_call_id ORDER BY fld_id DESC) [Row]
FROM table) LU ON A.fld_id = LU.fld_id
WHERE LU.[Row] = 1