SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08c54b3bfe684a89525beb5781f0a22ec42af52d46cf1db932016b5208e7d192' 
  AND token = 'HOXxAAHRZvkkjGUOxDmGkkbAB3ZF4qJ6QHwYnhh63o0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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