SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5bae0f909c45f0a242288270f0749c3b247647f8a0de33d6933f3a89f20a415' 
  AND token = 'Czo5Bok2XOSSskdXNN8QvICgfNISPcaPR8AtBem61E0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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