MySQL get first non null value after group by

Question

I have a large table with data that is not unique but needs to be. This table is a result of multiple union selects so is not an actual table. I cannot make it an actual table f

Answer 1

Try using MAX, like this:

SELECT
    email,
    MAX(`name`)
FROM
(
    SELECT
        email,
        `name`
    FROM
        multiple_tables_and_unions
) AS emails

GROUP BY email