SELECT fs.id, fs.fork_id, fs.bet_name,
f.bk1_name, f.bk2_name,
fs.real_cf, IF( fs.bk_name = f.bk1_name, bk1_coef, bk2_coef ) AS fork_cf,
(1/IF( fs.bk_name = f.bk1_name, bk1_coef, bk2_coef )-1/fs.real_cf) as BK2_CF_DIFF
FROM (

SELECT id, fork_id, bk_name, bet_name, event_name, cf, real_cf, bk1_forks_count, bk2_forks_count
FROM  `forks_stakes`
WHERE bk_id =  'FON'
AND vm_id
IN (
 '084_KZ_KISLOV',  '099_IK_SAIDZHONOV'
)
AND DATE( added_at ) >=  '2019-02-04'
GROUP BY event_name, bet_name
) AS fs
JOIN forks AS f ON ( f.id = fs.fork_id )