SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd02b12b41fc5811dd3035f17196f964e6156ef3884dc493d32e9caf30b6a2b94' 
  AND token = 'eHN1cTHG/T0wGdFw6tKnqLwbzVzKjFUJj9qsjUiZo1s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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