mysql join query order by two columns

Question

I am trying to join two tables and in both tables I have 2 same column names like agent_id and date both tables have agent_id and date actually I join tables based on agent_id a

Answer 1

    SELECT * FROM
    (
         SELECT sr.date
            FROM `sales_report` as sr
         UNION
         SELECT pm.date
            FROM `payments` as pm
        )
    ORDER BY date

I think this is what you wanted,Both sales_report and payments need be considered as a table.then sort it.