DOC-132 | Nested search with ArangoSearch Views

[Simran-B]

Basic description of nested search, limited to Views for now.

[Dronplane]

We state " Nested search (Enterprise Edition)" only in new-features but I suggest to mention EE in all places to avoid confusion.

[Simran-B]

@joerg84 Please clarify how to word the docs regarding Nested search support in Community vs. Enterprise Edition.

The question mark operator is available in all Editions, which means you can perform nested searches to some extent, but without index acceleration and there are some caveats:

• FOR doc IN coll FILTER doc.arr[? FILTER ...] is a kind of nested search and works in CE (but can be slow)
• FOR doc IN view FILTER doc.arr[? FILTER ...] is possible (can be slow) but the nested attributes need to be indexed using fields or includeAllFields in the View definition, otherwise, it will not find anything.
  UX issue: nested is silently ignored in CE, so you may be under the belief that the nested attributes were indexed but are in fact not
• FOR doc IN view SEARCH doc.arr[? FILTER ...] throws an error in CE (not implemented) and works in EE.
  UX issue: If you index the nested attributes with fields instead of nested in EE, it can never match something using such a query and View definition and should potentially warn the user about it.