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sql - combining results of two select statements

I'm using T-SQL with ASP.NET, and c# and i'm pretty new to SQL.

I was wondering how i could combine the results of two queries

Query1:

SELECT tableA.Id,  tableA.Name, [tableB].Username AS Owner, [tableB].ImageUrl, [tableB].CompanyImageUrl, COUNT(tableD.UserId) AS NumberOfUsers
 FROM tableD RIGHT OUTER JOIN 
         [tableB] INNER JOIN
         tableA ON [tableB].Id = tableA.Owner ON tableD.tableAId = tableA.Id
 GROUP BY tableA.Name, [tableB].Username, [tableB].ImageUrl, [tableB].CompanyImageUrl

Query2:

 SELECT tableA.Id,  tableA.Name, COUNT([tableC].Id) AS NumberOfPlans
 FROM   [tableC] RIGHT OUTER JOIN
           tableA ON [tableC].tableAId = tableA.Id
 GROUP BY tableA.Id, tableA.Name

Any help would be much appreciated. Thanks in advance

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by (71.8m points)

You can use a Union.

This will return the results of the queries in separate rows.

First you must make sure that both queries return identical columns.

Then you can do :

SELECT tableA.Id, tableA.Name, [tableB].Username AS Owner, [tableB].ImageUrl, [tableB].CompanyImageUrl, COUNT(tableD.UserId) AS Number
FROM tableD 
RIGHT OUTER JOIN [tableB] 
INNER JOIN tableA ON [tableB].Id = tableA.Owner ON tableD.tableAId = tableA.Id 
GROUP BY tableA.Name, [tableB].Username, [tableB].ImageUrl, [tableB].CompanyImageUrl

UNION

SELECT tableA.Id, tableA.Name,  '' AS Owner, '' AS ImageUrl, '' AS CompanyImageUrl, COUNT([tableC].Id) AS Number
FROM 
[tableC] 
RIGHT OUTER JOIN tableA ON [tableC].tableAId = tableA.Id GROUP BY tableA.Id, tableA.Name

As has been mentioned, both queries return quite different data. You would probably only want to do this if both queries return data that could be considered similar.

SO

You can use a Join

If there is some data that is shared between the two queries. This will put the results of both queries into a single row joined by the id, which is probably more what you want to be doing here...

You could do :

SELECT tableA.Id, tableA.Name, [tableB].Username AS Owner, [tableB].ImageUrl, [tableB].CompanyImageUrl, COUNT(tableD.UserId) AS NumberOfUsers, query2.NumberOfPlans
FROM tableD 
RIGHT OUTER JOIN [tableB] 
INNER JOIN tableA ON [tableB].Id = tableA.Owner ON tableD.tableAId = tableA.Id 


INNER JOIN 
  (SELECT tableA.Id, COUNT([tableC].Id) AS NumberOfPlans 
   FROM [tableC] 
   RIGHT OUTER JOIN tableA ON [tableC].tableAId = tableA.Id 
   GROUP BY tableA.Id, tableA.Name) AS query2 
ON query2.Id = tableA.Id

GROUP BY tableA.Name, [tableB].Username, [tableB].ImageUrl, [tableB].CompanyImageUrl

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