I have two tables:
Report
ReportId CreatedDate
1 2018-01-12
2 2018-02-12
3 2018-03-12
ReportSpecialty
SpecialtyId ReportId IsPrimarySpecialty
1 1 1
2 2 1
3 3 1
1 2 0
1 3 0
I am trying to write a query that will retrieve me the last 10 reports that were published. However, I need to get 1 report from each specialty. Assume there are 100 specialties, I can pass in as an argument any number of specialties, 10, 20, 5, 2, etc...
I'm trying to figure out a way where if I send it all specialties, it will get me the last 10 reports posted based on the last date created, but it won't give me 2 articles from same specialty. If I send it 10 specialties, then I will get 1 of each. If I send it 5, then I'll get 2 of each. If I send it 3 then I'll get 4 of 1 and 3 of other two.
I may need to write multiple queries for this, I'm trying to see if there is a way to do this on the SQL side of things? If there isn't, then how would I break down to multiple queries to get the result I want?
What I have tried is this, however I get multiple reports with same specialties:
SELECT TOP 10 r.ReportId, rs.SpecialtyId, r.CreatedDate
FROM Report r
INNER JOIN ReportSpecialty rs ON r.ReportId = rs.ReportId AND rs.IsPrimarySpecialty = 1
GROUP BY rs.SpecialtyId, r.AceReportid, r.CreatedDate
ORDER BY r.CreatedDate DESC
with cte as (
SELECT R.ReportId, R.CreatedDate, RS.SpecialtyId,
ROW_NUMBER() OVER (PARTITION BY RS.SpecialtyId
ORDER BY R.CreatedDate DESC) as rn
FROM Report R
JOIN ReportSpecialty RS
ON R.ReportId = RS.ReportId
AND RS.IsPrimarySpecialty = 1
WHERE RS.SpecialtyId IN ( .... ids ... )
)
SELECT TOP 10 *
FROM cte
ORDER BY rn, CreatedDate DESC
row_number will create a id for each speciality, so if you pass 3 speciality you will get something like this.
rn speciality_id
1 1
1 2
1 3
2 1
2 2
2 3
3 1
3 2
3 3
Related
I need some help with one query.
So, I already have CTE with the next data:
ApplicationID
CandidateId
JobId
Row
1
1
1
1
2
1
2
2
3
1
3
3
4
2
1
1
5
2
2
2
6
2
5
3
7
3
2
1
8
3
6
2
9
3
3
3
I need to find one job per candidate in a way, that this job was distinct for table.
I expect that next data from query (for each candidate select the first available jobid that's not taken by the previous candidate):
ApplicationID
CandidateId
JobId
Row
1
1
1
1
5
2
2
2
8
3
6
2
I have never worked with recursive queries in CTE, having read about them, to be honest, I don't fully understand how this can be applied in my case. I ask for help in this regard.
The following query returns the expected result.
WITH CTE AS
(
SELECT TOP 1 *,ROW_NUMBER() OVER(ORDER BY ApplicationID) N,
CONVERT(varchar(max), CONCAT(',',JobId,',')) Jobs
FROM ApplicationCandidateCTE
ORDER BY ApplicationID
UNION ALL
SELECT a.*,ROW_NUMBER() OVER(ORDER BY a.ApplicationID),
CONCAT(Jobs,a.JobId,',') Jobs
FROM ApplicationCandidateCTE a JOIN CTE b
ON a.ApplicationID > b.ApplicationID AND
a.CandidateId > b.CandidateId AND
CHARINDEX(CONCAT(',',a.JobId,','), b.Jobs)=0 AND
b.N = 1
)
SELECT * FROM CTE WHERE N = 1;
However, I have the following concerns:
The recursive CTE may extract too many rows.
The concatenated JobId may exceed varchar(max).
See dbfiddle.
I seek to find the maximum timestamp (ob.create_ts) for each group of marketid's (ob.marketid), joining tables obe (ob.orderbookid = obe.orderbookid) and market (ob.marketid = m.marketid). Although there are a number of solutions posted like this for a single table, when I join multiple tables, I get redundant results. Sample table and desired results below:
table: ob
orderbookid
marketid
create_ts
1
1
1664635255298
2
1
1664635255299
3
1
1664635255300
4
2
1664635255301
5
2
1664635255302
6
2
1664635255303
table: obe
orderbookentryid
orderbookid
entryname
1
1
'entry-1'
2
1
'entry-2'
3
1
'entry-3'
4
2
'entry-4'
5
2
'entry-5'
6
3
'entry-6'
7
3
'entry-7'
8
4
'entry-8'
9
5
'entry-9'
10
6
'entry-10'
table: m
marketid
marketname
1
'market-1'
2
'market-2'
desired results
ob.orderbookid
ob.marketid
obe.orderbookentryid
obe.entryname
m.marketname
3
1
6
'entry-6'
'market-1'
3
1
7
'entry-7'
'market-1'
6
2
10
'entry-10'
'market-2'
Use ROW_NUMBER() to get a properly filtered ob table. Then JOIN the other tables onto that!
WITH
ob_filtered AS (
SELECT
orderbookid,
marketid
FROM
(
SELECT
*,
ROW_NUMBER() OVER (
PARTITION BY
marketid
ORDER BY
create_ts DESC
) AS create_ts_rownumber
FROM
ob
) ob_with_rownumber
WHERE
create_ts_rownumber = 1
)
SELECT
ob_filtered.orderbookid,
ob_filtered.marketid,
obe.orderbookentryid,
obe.entryname,
m.marketname
FROM
ob_filtered
JOIN m
ON m.marketid = ob_filtered.marketid
JOIN obe
ON ob_filtered.orderbookid = obe.orderbookid
;
So as the title suggests I need to return the records from a table, where these records can belong to a group.
If there are several records in a group, return only the last one, and if the record does not belong to any group, return it together.
I have the following tables
(automation_execution) 1 --> n (automation_execution_action) 1 <---> 1 (workable)
I need to return workable table records, where they may or may not be linked to automation tables.
automation_execution
id
company_id
1
1
2
1
automation_execution_ations
id
automation_execution_id
workable_id
1
1
1
2
1
2
workable
id
company_id
status
created_at
1
1
finished
2022-01-19 19:48:24
2
1
processing
2022-01-19 18:00:24
3
1
processing
2022-01-19 18:00:24
4
1
processing
2022-01-19 18:00:24
In the example above, we have 4 workables, 1 and 2 belong to an automation and 3 and 4 do not, in this example I would need to return the record 2, 3 and 4.
So this SQL works:
select workables.*
from (
select workables.*,
automation_execution_actions.automation_execution_id,
row_number()
over (partition by automation_execution_actions.automation_execution_id order by workables.id desc) as rn
from workables
left join automation_execution_actions on automation_execution_actions.workable_id = workables.id
) as workables
where rn = 1
OR automation_execution_id IS NULL
order by id;
I wonder how to update order in this table for many-to-many relationship using SQL based on PostsId.
So my table now looks like:
I'm using SQL Server
BlogsId
PostsId
Order
1
1
1
0
2
2
1
0
3
3
2
0
3
4
2
0
3
5
3
0
3
6
3
0
but I want to update Order using SQL to this:
BlogsId
PostsId
Order
1
1
1
1
2
2
1
2
3
3
2
1
3
4
2
2
3
5
3
1
3
6
3
2
So for example: Blog with Id 3 is the first blog in Post with Id 2, Blog with Id 4 is the second Blog in Post with Id 2 and etc...
I've tried this:
DECLARE #myVar int
SET #myVar = 0
UPDATE [dbo].[BlogPost]
SET #myVar = [Order] = #myVar + 1
but then I got this:
BlogsId
PostsId
Order
1
1
1
1
2
2
1
2
3
3
2
3
3
4
2
4
3
5
3
5
3
6
3
6
So, I think I should do something in WHERE part (with Distinct maybe) but I don't know exactly what. I could write something in C# to do what I want but I don't know how to write something like this in SQL.
Physically maintaining an order or sequence of rows is rarely a good idea and can lead to data inconsistencies and other unforseen issues.
You would be better off creating a view that provides the additional Order column which you can do using row_number()
Create view BlogPosts as
select *,
Row_Number() over(partition by PostsId order by BlogsId) as [Order]
from blogpost;
If you really want to update an actual column in the table you could use a CTE
with b as (
select *,
Row_Number() over(partition by PostsId order by BlogsId) as seq
from blogpost
)
update b
set [Order] = seq;
You can update from a calculated row_number.
update t
set [Order] = rn
from (
select BlogsId, PostsId, [Order]
, rn = row_number() over (partition by PostsId order by BlogsId asc)
from BlogPost
) t
where ([Order] is null or [Order]!=rn);
select *
from BlogPost
order by BlogsId, PostsId
BlogsId
PostsId
Order
1
1
1
2
1
2
3
2
1
4
2
2
5
3
1
6
3
2
Demo on db<>fiddle here
I have the table below in an SQL database.
user rating
1 10
1 7
1 6
1 2
2 8
2 3
2 2
2 2
I would like to keep only the best two ratings by user to get:
user rating
1 10
1 7
2 8
2 3
What would be the SQL query to do that? I am not sure how to do it.
It will work
;with cte as
(select user,rating, row_number() over (partition by user order by rating desc) maxval
from yourtable)
select user,rating
from cte
where maxval in (1,2)