SQL - fetching a column that is not present in the table using SELECT clause

Question

I am trying to run a SELECT query to include a column that is not present in the table. How can I do it?

E.g. 

Id	Source
13972	PPI
13474	PPI
13393	PPI

My table has only the "Id" column; the "Source" column does not exist. 

Answer 1

You can use the following SQL to include the "Source" column.
 

SELECT Id, 'PPI' AS Source FROM tableName;