SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c007b56a7ff599f174748e22e973148a361728d570fa56bd2d536c5c3a5247c' 
  AND token = 'zNKAALJCuKMwfK4ybFwUXW1dh1HR+gBHi8O6x0cLuDQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}