How to calculate Sum of Count(*) in Mysql

Question

I have two tables that I count rows of them. For example;

Select count(*) FROM tbl_Events

Select count(*) FROM tbl_Events2

I need total count. How can I sum the result with a single statement?

Answer 1

select sum(cnt) from (
    select count(*) as cnt from tbl_events
    union all
    select count(*) as cnt from tbl_events2
) as x

Answer 2

Try this:

SELECT (Select count(*) FROM tbl_Events) + (Select count(*) FROM tbl_Events2)

Or (tested in MSSQL), this:

SELECT COUNT(*) 
FROM (SELECT * FROM tbl_Events 
      UNION ALL 
      SELECT * FROM tbl_Events2) AS AllEvents

I'd guess the first will lead to better performance because it has more obvious index options. Test to be sure, though.