Finding Similar Records with SQL

Question

Hello,

I have a SQL Server 2008 database with 2 tables. These tables are Address and Store. These tables are defined as

Address
--------
ID (int)
Line1 (nvarchar(255))
PostalCode (nvarchar(5))
City (nvarchar(255))
State (nvarchar(255))

Store
-----
ID (int)
LocationID (int)
Name

I am trying to find a list of stores that are located at the same address by Line1 and PostalCode. I need to ignore the ID because of duplicate records. I do not care about stores that are the only store at their location. Rather, I only want a list of stores that share a location. Unfortunately, I'm not sure how to do this.

How do I write a query that will only return records that are group to address at the same Line1 and PostalCode?

Thank you!

Answer 1

select s.ID, s.LocationID, s.Name, a.ID, a.Line1, a.PostalCode
from (
    select Line1 + ', ' + PostalCode as Line1PostalCode
    from Address a
    inner join Store s on a.ID = s.LocationID
    group by Line1+ ', ' + PostalCode
    having count(*) > 1
) ag
inner join Address a on ag.Line1PostalCode = a.Line1+ ', ' + a.PostalCode
inner join Store s on a.ID = s.LocationID

Answer 2

Is this what you want?

SELECT t1.*, s.* FROM
(SELECT Line1 ,PostalCode
FROM Address
GROUP BY Line1 ,PostalCode
HAVING COUNT(*) >1) t2
JOIN Address t1 ON t2.Line1  = t2.Line1 
AND t1.PostalCode = t2.PostalCode
JOIN  Store s on t1.ID = s.LocationID

Answer 3

This query uses a subquery to find all addresses with more than one store, and then uses that as the basis for selecting the stores to show.

WITH StoreAddress AS 
(
 SELECT * FROM Store s INNER JOIN Address a ON s.LocationID=a.LocationID
)
SELECT sa.* FROM StoreAddress sa INNER JOIN 
   (SELECT Line1, PostCode FROM StoreAddress
   GROUP BY Line1, PostCode
   HAVING Count(ID)>1) pairs 
ON pairs.Line1=sa.Line1 AND pairs.PostCode=sa.PostCode
ORDER BY sa.Line1, sa.PostCode

The query is sorted by Line1 and PostCode so that stores in the same location are shown together.