MySQL delete from table where column is empty

Question

I am trying to delete inserted data from table1 where a certain column from table2 (sname) is null. I am trying to achieve this through a left outer join but don't understand yet the fundamentals of it.

 table1 | anum  pnum 
         ===========
          001   001
          002   001
          003   002
          004   002


 table2 | anum  sname
         ============
          001   'cooking'
          001   'cleaning'
          002   'teaching'
          003   NULL

Any tips are highly appreciated.

Answer 1

To delete the rows in table1 where the corresponding value of sname in table2 is null, use this query:

DELETE table1
FROM table1
JOIN table2
  ON table2.anum = table1.anum
WHERE table2.sname IS NULL;

Answer 2

DELETE 
FROM table1

INNER JOIN table2 
  ON table1.anum = table2.anum

WHERE table2.sname IS NULL;