Thanks for your help and the critical thinking skills lesson, I greatly appreciate that. What I would like for the stored proc to return is all the rows (With...

But to answer your question ..

You do realise that you have not done this, don't you?

Let's say that the SSN exists in all but one of the tables.

What should the...

What are the parameters for the proc? Table name and SSN? Or just SSN?

Why do you think that the tables all need to be joined together?

Please explain your thinking behind removing and adding the IDENTITY column. Why not leave the IDENTITY column there during data load?

The PK is a separate matter, and there may be...

I don't have 2019 yet. Can you provide some screenshots showing what you are seeing?

What are you importing the package to? An SSIS project?

If I understand what you are asking, SET IDENTITY_INSERT may be what you are looking for.

Maybe the SQL Agent user does not have rights to create files in the backup folder ...

TOP 10 based on what metric? What are you ordering by?

No, that should not be an issue.

On your dataflow, what are the values...

Are you including any blocking transformations in your data flow?

This look very similar to this post. Why did you post again?

SELECT t.userid
      ,t.rid
      ,Total = SUM(TRY_CAST(t.value AS INT))
FROM temp t
GROUP BY t.userid
     ...

Do you mean by a stored proc? Or actually when the definition of the stored proc changes?

Is this client application running on the machines of multiple users? Do you need...

Another possibility

DECLARE @SSN2 VARCHAR(whatever);

SELECT @SSN2 = SSN
FROM dbo.BaseData bd
WHERE bd.SSN = @SSN;

SELECT SSN = ISNULL(@SSN2, 'No SSN Found');