MYSQL Left Join how do I select NULL values?
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This is a follow up question to my last question about table joins in MySQL

I need to be able to select the NULL values from the left joined table.

Here's my join:

    table1.id | table1.name | table2.id | table2.surname
    1 | John | 1 | Doe
    2 | Michael | 2 | Anderson
    3 | Anna | NULL | NULL
    4 | Sue | NULL | NULL

I would want to select WHERE table2.surname = NULL, but a query like this doesnt work

    SELECT table1.*,table2.* FROM table1 LEFT JOIN table2 ON table1.id=table2.id WHERE table2.surname=NULL

I can somewhat understand  the logic behind it not giving me any results, but there must be a way to grab them results?

Appreciate any help