SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec69804f624321bc356fe9d32343961555234c9542e79296136f82eeb27b17e6' 
  AND token = '2d0OvJgfPqvJW6czJ0kvbB4JMOuzoJcEcLGpx1pAe5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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