Yeah, like that!

Your sample data is messed up. I removed a bunch of columns so that I had a minimum to deal with. In a word, you need DelimitedSplit8K to do this...

I think you'd have to use LAG() to look at the previous visit for a given patient. Then use DATEDIFF() to get the days between the two dates, and if...

See https://docs.microsoft.com/en-us/sql/t-sql/queries/with-common-table-expression-transact-sql?view=sql-server-2017

See Example D.
USE AdventureWorks2012;
GO
WITH DirectReports (ManagerID, EmployeeID, Title, EmployeeLevel)
AS (   SELECT ManagerID,
       ...

script out all the constraints,
drop them all,
import data,
re-add the constraints by running script from step 1

If you use RIGHT([oldSSN],4) then the rest shouldn't matter, because you'll never get any of the dashes anyway, because they would be 5th from the right.

Got Google?
https://stackoverflow.com/questions/26771966/find-all-ssrs-reports-using-the-same-shared-dataset

Or company attorney, if they have one.

… and if the company gets security audited, that's going to be serious. and expensive.

Wait. I'm confused. You tell which are primary keys and foreign keys by looking at the table definitions. Inner joins vs outer joins - that's a join in a query:...

By looking at the indexes of the columns involved in the join. Could you give us an example of what you're looking at?
If a column participating in a join...

Odd. When I tried it without any of the SendMail part, it worked:
DECLARE @Recipients varchar(max)  = 'polkadot@email.com',
   @Subject varchar(max)       = 'Submission at ',
   ...

Take the nice barometer to the building manager and ask him?
https://sqlsunday.com/2016/02/11/median-and-percentile-in-tsql/

Tried HAVING yet?

Like I just said - what you see in Access or SQL Server's relationships window is a visual REPRESENTATION of the relationships. Which way you drag or whatever to create...