INSERT INTO Table from multiple tables

Question

Hey so I have a Junction table linking two unrelated tables. Both the tables have ID\'s. I need to select the ID from each table using WHERE<

Answer 1

Try this query:

     INSERT INTO C (aID, bID) 
     SELECT A.ID, B.ID 
     FROM A, B 
     WHERE A.Name='Me'
     AND B.Class='Math';

Answer 2

Another way can be

INSERT INTO c (aID, bID)
SELECT 
   (SELECT A.id FROM TableA A WHERE A.names = 'sometext'), 
   B.id FROM TableB B 
WHERE 
   B.x_name ='othertext';

Answer 3

Assuming there is only one value in each table for the given Name and Class, the easiest method is just to enclose your subqueries in ():

INSERT INTO c VALUES (
(SELECT ID from a where Name='Me'),
(SELECT ID from b where Class ='Math')
)

Demo on dbfiddle