T-SQL Stored Procedure with While Loop causing Errors in Primary Key Constraints

So I have this MS SQL Stored Procedure:

ALTER PROCEDURE [dbo].[Import_Agent_Client_Bucket_2010]
AS
BEGIN
    -- Loop Through Each Agent, Create a Bucket, Add their Clients to the Bucket
    DECLARE Agent_Cursor CURSOR FOR
    SELECT Agent_GUID, Agent_ID
    FROM  realforms_2011.dbo.Agent

    DECLARE @Agent_GUID uniqueidentifier
    DECLARE @Agent_ID int

    OPEN Agent_Cursor;
    FETCH NEXT FROM Agent_Cursor
    INTO @Agent_GUID, @Agent_ID;

    WHILE @@FETCH_STATUS = 0
        BEGIN
            -- Create a bucket for each agent
            DECLARE @cbPKTable TABLE (cbPK UNIQUEIDENTIFIER, cbID int) 

            INSERT INTO realforms_2011.dbo.Client_Bucket ([Description] ) OUTPUT inserted.Client_Bucket_GUID, inserted.Client_Bucket_ID INTO @cbPKTable
            SELE开发者_开发知识库CT ISNULL(a.First_Name, ' ') + ' ' + ISNULL(a.Last_Name, ' ') + '''s Clients'
            FROM  realforms_2011.dbo.Agent a
            WHERE Agent_GUID = @Agent_GUID

            DECLARE @Client_Bucket_GUID uniqueidentifier
            SELECT @Client_Bucket_GUID = cbPK FROM @cbPKTable

            DECLARE @Client_Bucket_ID int
            SELECT @Client_Bucket_ID = cbID FROM @cbPKTable

            INSERT INTO realforms_2011.dbo.Agent_Client_Bucket (Agent_GUID, Agent_ID, Client_Bucket_GUID, Client_Bucket_ID)
            VALUES (@Agent_GUID, @Agent_ID, @Client_Bucket_GUID, @Client_Bucket_ID)

            DECLARE @Client_GUID uniqueidentifier
            DECLARE @Client_ID int

            -- Get clients from the server (2010)
            DECLARE Client_Cursor CURSOR FOR
            SELECT C.Client_ID
            FROM realforms.dbo.Client C
                INNER JOIN realforms.dbo.Agent_Client AC ON AC.Client_ID = C.Client_ID
            WHERE AC.Agent_ID = @Agent_ID 
            ORDER BY C.Client_ID ASC

            OPEN Client_Cursor;
            FETCH NEXT FROM Client_Cursor
            INTO @Client_ID
            -- loop through each 2010 client
            WHILE @@FETCH_STATUS = 0
            BEGIN
                DECLARE @myNewPKTable TABLE (myNewPK UNIQUEIDENTIFIER) 

                INSERT INTO realforms_2011.dbo.Client (Client_ID,Name,Secondary_Name,[Address],Address_2,City_State_Zip,Phone,Email_Address,Secondary_Email_Address,Create_Date,Last_Change_Date,[Status],File_Under,[Year]) OUTPUT inserted.Client_GUID INTO @myNewPKTable
                SELECT c.Client_ID,Name,Secondary_Name,[Address],Address_2,City_State_Zip,Phone,Email_Address,Secondary_Email_Address,Create_Date,Last_Change_Date,[Status],File_Under,2010
                FROM realforms.dbo.Client C
                    INNER JOIN realforms.dbo.Agent_Client AC ON AC.Client_ID = C.Client_ID
                WHERE AC.Agent_ID = @Agent_ID AND C.Client_ID = @Client_ID

                SELECT @Client_GUID = myNewPK FROM @myNewPKTable

                INSERT INTO realforms_2011.dbo.Client_Bucket_Client (Client_Bucket_GUID, Client_GUID, Client_ID, Client_Bucket_ID, [Year])
                VALUES (@Client_Bucket_GUID, @Client_GUID, @Client_ID, @Client_Bucket_ID, 2010)

                PRINT 'Client Bucket GUID: '
                PRINT @Client_Bucket_GUID
                PRINT 'Client GUID: '
                PRINT @Client_GUID

                FETCH NEXT FROM Client_Cursor
                INTO @Client_ID;
            END;

            CLOSE Client_Cursor;
            DEALLOCATE Client_Cursor;

            FETCH NEXT FROM Agent_Cursor
            INTO @Agent_GUID, @Agent_ID;
       END;
    CLOSE Agent_Cursor;
    DEALLOCATE Agent_Cursor;

END

But I get an error message on just a very few of the items, it says

Msg 2627, Level 14, State 1, Procedure Import_Agent_Client_Bucket_2010, Line 71 Violation of PRIMARY KEY constraint 'Client_Bucket_Client_PK'. Cannot insert duplicate key in object 'dbo.Client_Bucket_Client'. The statement has been terminated.

EDIT:

OK, I see what you're doing there, I apologize for missing the OUTPUT statement. Based on that information, it seems like the code could break if a record is not inserted into the Client table in the line right before SELECT @Client_GUID = myNewPK FROM @myNewPKTable. If no record is inserted, you would wind up grabbing the GUID from the previous record and when you go to insert that it would cause the PK violation. You might have to check to make sure that records are being inserted into the Client table.

ORIGINAL ANSWER:

It looks like you're declaring a table:

DECLARE @myNewPKTable TABLE (myNewPK UNIQUEIDENTIFIER)

But then you never put anything into it, so this statement must return null:

SELECT @Client_GUID = myNewPK FROM @myNewPKTable

EDIT:

Why not just do this? I don't see why the table @myNewPKTable is even being created.

SET @Client_GUID = NEWID()

EDIT:

I think the reason you are getting the primary key violation is because @Client_Bucket_GUID is null. At the beginning of the procedure, there is this code:

-- Create a bucket for each agent
DECLARE @cbPKTable TABLE (cbPK UNIQUEIDENTIFIER, cbID int) 

...

DECLARE @Client_Bucket_GUID uniqueidentifier
SELECT @Client_Bucket_GUID = cbPK FROM @cbPKTable

After this code is run @Client_Bucket_GUID will always be null. Again, you would have to insert records into @cbPKTable if you wanted to get anything out of it. If you're trying to create a new UNIQUEIDENTIFIER and store it in @Client_Bucket_GUID, just use the NEWID() function.