Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '835f4e9c0a319947277ee85d12e47f915d84e8a0d35b0c76de89db657bd3e0c4' 
  AND token = 'm8t6rO8XIJbQnmwQJyk4igiwI6ZM2sEnPlmgkl2Cz4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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