Sql – Finding rows with same values in multiple columns

sqlsql server

I am trying to find rows that have duplicate values, but only based off of a select number of columns, not a single column or the entire row. For example, if my table looked like this:

ID     Address    State    Name
-------------------------------
0      7 Brown    NY       John
1      3 Red      WX       Jane
2      7 Brown    WX       Ted
3      7 Brown    NY       Fred

My question would be:

Find all ID's for rows where the row's Address and State field matched another row's Address and State field.

The answer to this query would be:

ID    Address    State    Name
------------------------------
0     7 Brown    NY       John
3     7 Brown    NY       Fred

Any Ideas?

Suggestions:
How to select multiple columns values same rows from single table

Best Answer

Try the following:

SELECT A.*
FROM YourTable A
INNER JOIN (SELECT Address, State
            FROM YourTable
            GROUP BY Address, State
            HAVING COUNT(*) > 1) B
ON A.Address = B.Address AND A.State = B.State

Related Solutions

Sql – How to concatenate text from multiple rows into a single text string in SQL Server

If you are on SQL Server 2017 or Azure, see Mathieu Renda answer.

I had a similar issue when I was trying to join two tables with one-to-many relationships. In SQL 2005 I found that XML PATH method can handle the concatenation of the rows very easily.

If there is a table called STUDENTS

SubjectID       StudentName
----------      -------------
1               Mary
1               John
1               Sam
2               Alaina
2               Edward

Result I expected was:

SubjectID       StudentName
----------      -------------
1               Mary, John, Sam
2               Alaina, Edward

I used the following T-SQL:

SELECT Main.SubjectID,
       LEFT(Main.Students,Len(Main.Students)-1) As "Students"
FROM
    (
        SELECT DISTINCT ST2.SubjectID, 
            (
                SELECT ST1.StudentName + ',' AS [text()]
                FROM dbo.Students ST1
                WHERE ST1.SubjectID = ST2.SubjectID
                ORDER BY ST1.SubjectID
                FOR XML PATH ('')
            ) [Students]
        FROM dbo.Students ST2
    ) [Main]

You can do the same thing in a more compact way if you can concat the commas at the beginning and use substring to skip the first one so you don't need to do a sub-query:

SELECT DISTINCT ST2.SubjectID, 
    SUBSTRING(
        (
            SELECT ','+ST1.StudentName  AS [text()]
            FROM dbo.Students ST1
            WHERE ST1.SubjectID = ST2.SubjectID
            ORDER BY ST1.SubjectID
            FOR XML PATH ('')
        ), 2, 1000) [Students]
FROM dbo.Students ST2

Sql-server – Select columns from result set of stored procedure

Can you split up the query? Insert the stored proc results into a table variable or a temp table. Then, select the 2 columns from the table variable.

Declare @tablevar table(col1 col1Type,..
insert into @tablevar(col1,..) exec MyStoredProc 'param1', 'param2'

SELECT col1, col2 FROM @tablevar

Best Answer

Related Solutions

Sql – How to concatenate text from multiple rows into a single text string in SQL Server

Sql-server – Select columns from result set of stored procedure

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