SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a85e604e212e43b56259d5421ae94b991a76338821900c91250a57690dfeca59' 
  AND token = 'QDxB7zHaJdeSvQnOf5kF3l2EmBMhmxP/h2A1J51aIVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}