SQL WHERE versus HAVING Example 

Got this question on the interview. It must be the best explanation I've seen.

Thank You Very Much Very Helpful and simplified.:-)

Excellent explanation! Helped me a lot.

Thank you very much for the tutorial!!! It is very good!!! ¡Pura Vida!

Thank you so much that cleared my cloud.

Thank you! Very helpful and well explained! :)

Very helpful. Thanks!

Perfect, thank you.

Thank you ..its very use full :)

we can also use nested query

On the last query what could you add to return NULL values for the regions that have not sold "widget"?

really helpful..Thank you!