SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8245aadee6b7632b64e3da4043e551e1e09229a8f4c491fb92f06a01ab2963d' 
  AND token = 'SZqBQvUf/IhXkwF65vDnjpv4+tqlfTbu1NgViX2Jphk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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