Investigate changes in SERVER-1599

Description

Change Description:

Update command now supports index hints, similar to the count command and aggregation pipeline hints. Hint values may be the key value pattern or index name.

SERVER ticket description:

Support a way to pass a hint to update command to use a specific index for update query filter. Work done under this ticket will not prevent misuse of hinting, as reported by SERVER-26413.

Original description:
Change the behavior on the server for update to look for the special fields: $query, $sortby, $limit, $hint. If these are found treat them the same as the Op_Query does.

This will allow sorting (so you can update the right element), $limit (so you can just update some of them), $hint (so you can force the right index) in addition to the normal $query part.

This should be backwards compatible. It will either be a $query + other $ options, or just the query, without options (like it is now).

Scope of changes

Impact to Other Docs

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)