I have 2 table in my database that tables are in relationship with foreign key
I want to select all records from main table and then select count of each row in another table than have same ID from main table I tried to create a select query but it is not work correctly
this query return all records from main table + count of all records from next table(not count of each row in relationship)
SELECT tblForumSubGroups_1.id, tblForumSubGroups_1.GroupID,
tblForumSubGroups_1.SubGroupTitle, tblForumSubGroups_1.SubGroupDesc,
(SELECT COUNT(dbo.tblForumPosts.id) AS Expr1
FROM dbo.tblForumSubGroups INNER JOIN dbo.tblForumPosts ON
dbo.tblForumSubGroups.id = dbo.tblForumPosts.SubGroupID) AS Expr1
FROM dbo.tblForumSubGroups AS tblForumSubGroups_1 INNER JOIN
dbo.tblForumPosts AS tblForumPosts_1 ON tblForumSubGroups_1.id
= tblForumPosts_1.SubGroupID
SELECT tblForumSubGroups_1.id, tblForumSubGroups_1.GroupID, tblForumSubGroups_1.SubGroupTitle, tblForumSubGroups_1.SubGroupDesc,
COUNT(tblForumPosts_1.id) AS Expr1
FROM dbo.tblForumSubGroups AS tblForumSubGroups_1
INNER JOIN dbo.tblForumPosts AS tblForumPosts_1 ON tblForumSubGroups_1.id = tblForumPosts_1.SubGroupID
GROUP BY tblForumSubGroups_1.id, tblForumSubGroups_1.GroupID, tblForumSubGroups_1.SubGroupTitle, tblForumSubGroups_1.SubGroupDesc
I would suggest cross apply as you can do a lot more things with it ...
SELECT t1.id,
t1.GroupID,
t1.SubGroupTitle,
t1.SubGroupDesc,
t2.val
FROM dbo.tblForumSubGroups AS t1
cross apply (SELECT COUNT(*)
FROM dbo.tblForumPosts as t2
WHERE t1.id = t2.SubGroupID) x(val)
Do not mix sub-query and join logic. Use only one of them. I prefer sub-select.
SELECT tblForumSubGroups_1.id,
tblForumSubGroups_1.GroupID,
tblForumSubGroups_1.SubGroupTitle,
tblForumSubGroups_1.SubGroupDesc,
(SELECT COUNT(*)
FROM dbo.tblForumPosts
WHERE dbo.tblForumSubGroups.id = dbo.tblForumPosts.SubGroupID) AS Expr1
FROM dbo.tblForumSubGroups AS tblForumSubGroups_1
Just to supply another answer though I believe the cross apply is likely the best option:
SELECT
A.id, A.GroupID, A.SubGroupTitle, A.SubGroupDesc,
B.IDCount AS Expr1
FROM dbo.tblForumSubGroups A
INNER JOIN (
Select SubGroupID, Count(ID) as IDCount
from dbo.tblForumPosts
Group By SubGroupID
) B On A.ID = B.SubGroupID
Related
I have the below code in SQL Server and I want the same output but as a view. How do I write a view to give this output? I want the result from the first query basically along with the count of distinct people id for each occupancy id but I can't use group by in that query.
Thanks in advance!
SELECT DISTINCT
pp.PeopleID,
od.OccupancyID,
pp.Gender
INTO
t1
FROM
dimPeople AS pp
LEFT JOIN
OccupanciesPeople AS op ON op.PeopleID = pp.PeopleID
AND op.CompanyID = pp.CompanyID
LEFT JOIN
OccupancyDetail AS od ON op.OccupancyID = od.OccupancyID
AND op.CompanyID = od.CompanyID
WHERE
od.OccupancyEndDate IS NULL
AND op.DateLeftOccupancy IS NULL
AND pp.DateOfDeath IS NULL
SELECT
OccupancyID, COUNT(DISTINCT peopleID) AS PeopleCount
INTO
t2
FROM
t1
GROUP BY
OccupancyID
SELECT
t1.*,
t2.PeopleCount, t2.[HouseHold Person]
FROM
t1
JOIN
t2 ON t1.occupancyID = t2.OccupancyID
DROP TABLE t1
DROP TABLE t2
If those queries work the way you want (spoiler: they don't - you don't define t2.[HouseHold Person] when you create t2), you could replace the 2 "into" tables with Common Table Expressions and get your results.
CREATE VIEW dbo.MyView AS
WITH t1 AS (
SELECT DISTINCT
pp.PeopleID,
od.OccupancyID,
pp.Gender
FROM
dimPeople AS pp
LEFT JOIN
OccupanciesPeople AS op ON op.PeopleID = pp.PeopleID
AND op.CompanyID = pp.CompanyID
LEFT JOIN
OccupancyDetail AS od ON op.OccupancyID = od.OccupancyID
AND op.CompanyID = od.CompanyID
WHERE
od.OccupancyEndDate IS NULL
AND op.DateLeftOccupancy IS NULL
AND pp.DateOfDeath IS NULL
), t2 as (
SELECT
OccupancyID, COUNT(DISTINCT peopleID) AS PeopleCount
FROM
t1
GROUP BY
OccupancyID
)
SELECT
t1.PeopleID,
t1.OccupancyID,
t1.Gender,
t2.PeopleCount
FROM
t1
JOIN
t2 ON t1.occupancyID = t2.OccupancyID;
I don't know, if I made good title, but please let me visualize this.
So I have two tables and for given case I need to select row where payment currency was ONLY in EUR.
Correct document Id's will be: 2, 3, 4, 5
These are overall bigger tables with 900k+ records.
Can you please suggest me how query should look?
use correlated subquery with not exists
select distinct a.document_id from tablename a inner join tablename b b on a.document_id=b.payment_docid
where not exists
(select 1 from tablename b1 where b1.payment_docid=b.payment_docid and currency<>'EUR')
Try this query:
select payment_docId from MyTable
group by payment_docId
having max(currency) = 'EUR'
and min(currency) = 'EUR'
or you could use having count(*) = 1 with min or max as well.
use corelated subquery
select t1.* from table2 as t1
where exists( select 1 from table2 t2 where t1.payment_docid=t2.payment_docid
having count(distinct currency)=1)
and currency='EUR'
It is possible to use INNER JOIN with the following conditions to get all rows:
SELECT
pd.payment_doc_id
, pd.currency
FROM DocTable dt
INNER JOIN PaymentDocs pd
ON dt.document_id = pd.payment_doc_id AND pd.currency IN ('EUR')
If you want distinct rows, then you can apply operator GROUP BY:
SELECT
pd.payment_doc_id
, pd.currency
FROM DocTable dt
INNER JOIN PaymentDocs pd
ON dt.document_id = pd.payment_doc_id AND pd.currency IN ('EUR')
GROUP BY pd.payment_doc_id
, pd.currency
Aggregation is the only efficient want :
select doc_id
from table t
group by doc_id
having min(currency) = max(currency) and min(currency) = 'EUR';
I have Item and Exam tables -
My desire result -
I tried a lot but I am unable to join Exam table to Item table based on Code group.
Is it possible to cross join or any other join for these two tables to get the desire result?
You can try this
SELECT A.Code, i.Item, A.Exam
FROM
(
SELECT Code,e.Exam
FROM Item i
CROSS JOIN Exam e
GROUP BY Code,e.Exam
) A
LEFT JOIN Item i ON i.Code= A.Code AND i.Exam = A.Exam
I don't see a way around generating the missing data. The calendar table approach would be to cross join all codes with all exams. Then, left join this table to Item and order to get the result you want:
WITH cte AS (
SELECT *
FROM (SELECT DISTINCT Code FROM Item) AS C
CROSS JOIN Exam
)
SELECT
t1.Code,
t2.Item,
t1.Exam
FROM cte t1
LEFT JOIN Item t2
ON t1.Code = t2.Code AND
t1.Exam = t2.Exam
ORDER BY
t1.Code,
CASE WHEN t2.Item IS NOT NULL THEN 0 ELSE 1 END,
t1.Exam
Demo here:
Rextester
This should produce what you need. I am using UNION to combine CROSS JOIN and item table and then group by to ensure NULLs are removed.
SELECT code, max(item) as item, exam
FROM
(SELECT distinct i.code, null as item, e.exam FROM exam e cross join item i
union all
SELECT code, item, exam
FROM item) u
group by code, exam
order by code, exam
I know, in a Group By you can't Select a field that is not in an aggregate function or the GROUP BY clause.
However, There must be a workaround using joins or something else.
I have TWO tables BMP_VISITS_SITES and BMP_VISITS_COMMENTS which are connected by StationID in a one-to-many relationship. One Site can have many comments.
I'm trying to write a query that returns all Sites and the latest (only 1) comment. I have a "working" query but it only returns two columns which are in either an aggregate function or group by.
Here is my "working" query:
select a.StationID,
MAX(b.[dateobserved]) as LastDateObserved,
a.Status
from BMP_VISITS_SITES a
left outer join BMP_VISITS_COMMENTS as b
on a.[StationID] = b.[StationID]
group by a.StationID;
But how can I access all the columns in both tables?
I've tried inner joins with 1/2 success. When I join my BMP_VISITS_SITES to the above query I get all the fields of the table (t1). Great, but as soon as I try joining on BMP_VISITS_COMMENTS (t3) I get more results than I should.
select t1.*, t2.*
--,t3.*
from BMP_VISITS_SITES t1
inner join (
select a.StationID, MAX(b.[dateobserved]) as LastDateObserved from BMP_VISITS_SITES a
left outer join BMP_VISITS_COMMENTS as b
on a.[StationID] = b.[StationID]
group by a.StationID
) t2 on t2.StationID = t1.StationID
--inner join sde.BMP_VISITS_COMMENTS t3 on t3.StationID = t2.StationID;
SELECT a.*, b.* FROM
BMP_VISITS_SITES a
OUTER APPLY
(
SELECT TOP 1 *
FROM BMP_VISITS_COMMENTS b
WHERE b.StationID = a.StationID
ORDER BY LastDateObserved DESC
) b
You can use apply to get the last comment record and return all fields from both sides of the query.
Use row_number()
select *
from
(
select a.StationID,
a.Status,
b.*,
row_number() over (partition by a.stationid, a.status order by b.[dateobserved] desc) as rn
from BMP_VISITS_SITES a
left outer join BMP_VISITS_COMMENTS as b
on a.[StationID] = b.[StationID]
) v
where rn = 1
Not quite sure how to ask this, but I have 2 tables that are related in a 1 to many relationship, I need to select all records in the "1" table that have less than three records in the "many' table.
select b.foreignkey,count(b.foreignkey) as bidcount
from b
where b.foreignkey in (select a.id from a) and bidcount< 3
group by b.foreignkey
this doesn't work at all I know but I am at a loss how to do this.
I need to in the end select all the records from the "a" table based on this criteria. Sorry if that is confusing!
Just using your code, not tested:
SELECT
b.foreignkey,
count(b.foreignkey) as bidcount
FROM
b
WHERE
b.foreignkey IN (SELECT a.id FROM a)
GROUP BY
b.foreignkey
HAVING
count(b.foreignkey) < 3
Try this:
SELECT t1.id,COUNT(t2.parentId)
FROM table1 as t1
INNER JOIN table2 as t2
ON t1.id = t2.parentId
GROUP BY t1.id
HAVING COUNT(t2.parentId) < 3
You didn't mention which version of SQL Server you're using - if you're on SQL Server 2005 or newer, you could use this CTE (Common Table Expression):
;WITH ChildRows AS
(
SELECT A.Id, COUNT(b.Id) AS 'BCount'
FROM
dbo.TableA A
INNER JOIN
dbo.TableB B ON B.TableAId = A.Id
)
SELECT A.*, R.BCount
FROM dbo.TableA A
INNER JOIN ChildRows R ON A.Id = R.Id
The inner SELECT lists the Id columns from TableA and the count of the child rows associated with those (using the INNER JOIN to TableB) - and the outer SELECT just builds on top of that result set and shows all fields from table A (and the count from the B table)
if you want to return all fields of your (1) table in one query, I suggest you consider using CROSS APPLY:
SELECT t1.* FROM table_1 t1
CROSS APPLY (SELECT COUNT(*) cnt FROM Table_Many t2 WHERE t2.fk = t1.pk) a
where a.cnt < 3
in some particular cases, based on your indices and db structure, this query may run 4 times faster than the GROUP BY method
you have posted this question in sql server, I have a answer in oracle database system (don't know whether it will run in sql server as well or not)
this is as follow-
select [desired column list] from
(select b.*, count(*) over (partition by b.foreignkey) c_1
from b
where b.foreignkey in (select a.id from a) )
where c_1 < 3 ;
i hope it should work on sql server as well...
if not please let me update ..