SELECT statements have a different number of columns - mysql

Question

I have tried using the code below and it says
The used SELECT statements have a different number of columns
because distance column in added is more in 2nd query .How do I resolve something like this or can I get the order right without distance column?I really appreciate any help.THanks in Advance.
SELECT * FROM
(
SELECT * FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
WHERE u.empid = 123
UNION
SELECT * ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(-122) )+ sin( radians(37) ) * sin( radians( lat ) ) ) ) AS distance
FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
HAVING distance < 25
ORDER BY distance
) a
ORDER BY timestamp DESC

Answer 1

It's because your 1st SELECT and 2nd SELECT have varying number of columns, since you introduced Distance in 2nd SELECT.
So try making Distance in 1st query null or 0 as follows.
SELECT * FROM
(
SELECT *, 0 as Distance
FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
WHERE u.empid = 123
UNION
SELECT *, ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(-122) )+ sin( radians(37) ) * sin( radians( lat ) ) ) ) AS distance
FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
HAVING distance < 25
ORDER BY distance
) a
ORDER BY timestamp DESC

Answer 2

You would fix this by adding distance to the first query:
SELECT * FROM
(
SELECT *, NULL as distance FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
WHERE u.empid = 123
UNION
SELECT *, ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(-122) )+ sin( radians(37) ) * sin( radians( lat ) ) ) ) AS distance
FROM user u
INNER JOIN employee e ON (u.empid = e.empid)
INNER JOIN awards a ON (u.empid = a.empid)
HAVING distance < 25
ORDER BY distance
) a
ORDER BY timestamp DESC;