SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d3d9fd1897b5be2387980c9446604dea7a66e5d07f5495e555b1c329b657d2b' 
  AND token = 'ZNHlvoP3kHsELEXayfEBNiEa/oWhi8FYJI11htWYbHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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