Count all records that does not exist to other table - SQL Query

Question

I have two(2) tables and I\'m trying to count all records from Table1 and Table1_delta were pagename from Table1_delta is not yet listed into Table1. Incase pagename from Ta

Answer 1

Here is an alternative solution using joins:

SELECT COUNT(*)
FROM Table1_delta t1 LEFT JOIN Table1 t2
ON t1.pagename = t2.pagename
WHERE t2.status IS NULL OR t2.status = 1

Here is what the temporary table from the above query looks like:

+-----------+--------+
| pagename  | status |
+-----------+--------+
| pagename1 |  2     |    # this row is NOT counted
| pagename2 |  1     |    # +1 this row has status = 1 and is counted
| pagename3 |  null  |    # +1 this row has status = null and is counted
| pagename4 |  null  |    # +1 this row is also null and is counted
+-----------+--------+

Check out the link below for a running demo.

SQLFiddle