Clarify documentation of scroll_id
* Clarify documentation of scroll_id
The Scroll API may return the same scroll ID for multiple requests due to server side state. This is not clear from the current documentation.
* Further clarify scroll ID return behaviour
@@ -78,9 +78,9 @@ returned with each batch of results. Each call to the `scroll` API returns the
next batch of results until there are no more results left to return, ie the
`hits` array is empty.
-IMPORTANT: The initial search request and each subsequent scroll request
-returns a new `_scroll_id` -- only the most recent `_scroll_id` should be
-used.
+IMPORTANT: The initial search request and each subsequent scroll request each
+return a `_scroll_id`, which may change with each request -- only the most
+recent `_scroll_id` should be used.
NOTE: If the request specifies aggregations, only the initial search response
will contain the aggregations results.
