How to confirm that primary key is not duplicated

Hello Experts,

I have table like this (ServiceID, ServiceName) that have multiple records duplicated and I want to check if there is one "ServiceID" associated with more  than one "ServiceName" records.

Thanks a lot.
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Ryan ChongCommented:
>>I want to check if there is one "ServiceID" associated with more  than one "ServiceName" records.

to find out duplicate records, try run a query like:

select ServiceID, ServiceName from yourTable
Group By ServiceID, ServiceName
Having count(ServiceID) > 1

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to avoid your ServiceID to be duplicated, you could set the Is Identity property to true.
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setting properties
Vitor MontalvãoMSSQL Senior EngineerCommented:
How to confirm that primary key is not duplicated
Just the fact to be a Primary Key is enough to assure that can't be duplicated. If there are duplicates then it means that a Primary Key doesn't exists.
HarreniAuthor Commented:
Thanks Ryan Chong.
Your query showing me if the primary is duplicated only, But I want to figure out all "ServiceName" that are associated with specific primary key.
I got the data which is not really normalized and found that there are some primary key associated with same service name.
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Ryan ChongCommented:
>>But I want to figure out all "ServiceName" that are associated with specific primary key.
is that mean the "ServiceName" tend to be unique and you wish to find out all ServiceID that has same "ServiceName" ?
select ServiceID, ServiceName from yourTable where serviceID=???

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replace ??? with your specific serviceID value you want to check
Vitor MontalvãoMSSQL Senior EngineerCommented:
It's better you post some sample data because you're missunderstanding what's a Primary Key.
HarreniAuthor Commented:
Yes Ryan, you're right.

Here is an example of my data:

Ryan ChongCommented:
emmmmm, you could try:

select a.* from
yourTable a
inner join
select ServiceID from yourTable
Group By ServiceID 
Having count(ServiceID) > 1
) b
on a.ServiceID = b.ServiceID
order by a.ServiceID, a.ServiceName

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Vitor MontalvãoMSSQL Senior EngineerCommented:
ServiceID isn't your Primary Key (PK) otherwise it wouldn't let you have duplicate ServiceIDs. Or you don't have a PK at all or the PK is [ServiceID + ServiceName].

You can have the Service Names associated to a ServiceID as a list using the following query:
	STUFF((SELECT ',' + ServiceName
		FROM YourTableNameHere T2
		WHERE T1.ServiceID= T2.ServiceID
	), 1, 1, '' ) 
FROM YourTableNameHere T1

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HarreniAuthor Commented:
Thanks for your help, your way is showing what's needed but with duplicated ServiceIDs'.

You give me what I need exactly. Can you just do it using "join" relation instead of XML Path??
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