SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '888847557e56292be1a9063c17310f298697370db195d7efaf277c66735d6adb' 
  AND token = 'Se0NQtDsMRzL49lryFEBlVP9YmKQjIuQ38LlhGlxnp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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