I have to select CompanyId column only from the following SQL;
select CompanyId,
row_number() over (partition by [GradeName] order by [TankNumber] ) rn
from [Data_DB].[dbo].[Company] where CompanyCode='ASAAA'
In the SQL, I try to figure out duplicate records, and from another table i want to delete some records based on the CompanyId from above query.
that is;
delete from [[dbo].ObservationData
where CompanyId in (select CompanyId,
row_number() over (partition by [GradeName] order by [TankNumber] ) rn
from [Data_DB].[dbo].[Company] where CompanyCode='ASAAA')
How can I modify above query?
Assuming you don't care which duplicate gets retained or deleted, you may try using a deletable CTE here:
WITH cte AS (
SELECT *,
ROW_NUMBER() OVER (PARTITION BY [GradeName] ORDER BY [TankNumber]) rn
FROM [Data_DB].[dbo].[Company]
WHERE CompanyCode = 'ASAAA'
)
DELETE
FROM cte
WHERE rn > 1;
This answer arbitrarily retains the "first" duplicate, with first being defined as the record with the earliest row number.
delete from [[dbo].ObservationData
where CompanyId in (select CompanyId from (select CompanyId,
row_number() over (partition by [GradeName] order by [TankNumber] ) rn
from [Datat_DB].[dbo].[Company] where CompanyCode='ASAAA') a where rn > 1 ;
Related
As you can see below, I'm able to select all the row_numbers that are duplicates. I identified them using a window function ROW_NUMBER()
Although I want to delete them from the database.
How can I change my code to remove the duplicates identified, as I'm currently getting an error
WITH RowNumCTE AS (
SELECT *,
ROW_NUMBER() OVER (
PARTITION BY ParcelID,
PropertyAddress,
SalePrice,
SaleDate,
LegalReference
ORDER BY
UniqueID
) row_num
FROM housing_data
)
SELECT *
FROM RowNumCTE
WHERE row_num > 1
Duplicates are identified as having a row_number greater than 1.
Thanks
I found the solution. I used
DELETE FROM housing_data
WHERE ROWID NOT IN (
SELECT MIN(ROWID)
FROM housing_data
GROUP BY ParcelID, PropertyAddress, SalePrice, SaleDate, LegalReference
);
I have a table where the primary key is a composite key of ID and date. Is there a way that I can delete a single row where ID matches and the date is the latest date?
I am new to SQL, so I have tried a few things, but I either don't get the results I am looking for or cant get the syntax correct
DELETE FROM Master
WHERE ((Identifier = 'SomeID')
AND (EffectiveDate = MAX(EffectiveDate));
There are multiple columns with the same ID, but different dates, ie.
ID EffectiveDate
-------------------------
A '2019-09-18'
A '2019-09-17'
A '2019-09-16'
Is there a way I can delete only the row with A | '2019-09-18'?
You can use window functions and an updatable CTE:
with todelete as (
select t.*, row_number() over (partition by id order by effective_date desc) as seqnum
from t
)
delete from todelete
where seqnum = 1;
Note: If you want to limit this to a single id, then be sure to include a where id = 'a' in either the subquery or outer query.
use row_number()
delete from (select *, row_number() over(partition by id order by effectivedate desc) rn from table_name
) a where a.rn=1
A correlated subquery might get the job done:
DELETE FROM Master
WHERE
Identifier = 'SomeID'
AND EffectiveDate = (
SELECT MAX(EffectiveDate) FROM Master WHERE Identifier = 'SomeID'
)
;
Use the CTE Function to Delete the Row but the below Query will not delete the Record of Max Date of those ID's where Single Record exist against that.
with todelete as (
select t.*, row_number() over (partition by id order by effective_date desc) as seqnum
from t
)
delete from todelete
where seqnum = 1 and id in(select distinct id from todelete where seqnum<>1)
With correlated subquery for all IDs:
delete table1
from table1 t1
where t1.EffectiveDate =
(
select max(t2.EffectiveDate)
from table1 t2
where t2.ID = t1.ID
)
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
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
Here are the columns in my table:
Id
EmployeeId
IncidentRecordedById
DateOfIncident
Comments
TypeId
Description
IsAttenIncident
I would like to delete duplicate rows where EmployeeId, DateOfIncident, TypeId and Description are the same - just to clarify - I do want to keep one of them. I think I should be using the OVER clause with PARTITION, but I am not sure.
Thanks
If you want to keep one row of the duplicate-groups you can use ROW_NUMBER. In this example i keep the row with the lowest Id:
WITH CTE AS
(
SELECT rn = ROW_NUMBER()
OVER(
PARTITION BY employeeid, dateofincident, typeid, description
ORDER BY Id ASC), *
FROM dbo.TableName
)
DELETE FROM cte
WHERE rn > 1
use this query without using CTE....
delete a from
(select id,name,place, ROW_NUMBER() over (partition by id,name,place order by id) row_Count
from dup_table) a
where a.row_Count >1
You can use the following query. This has an assumption that you want to keep the latest row and delete the other duplicates.
DELETE [YourTable]
FROM [YourTable]
LEFT OUTER JOIN (
SELECT MAX(ID) as RowId
FROM [YourTable]
GROUP BY EmployeeId, DateOfIncident, TypeId, Description
) as KeepRows ON
[YourTable].ID = KeepRows.RowId
WHERE
KeepRows.RowId IS NULL