Improve EntityRef performance for large EntitySets

[Daniel-Svensson]

When lots of rows are in-memory, calculating foreign key relationships can become very slow. Adding indexes to the EntitySet would greatly help performance in those situations.

This work item was migrated from CodePlex

CodePlex work item ID: '6'
Vote count: '3'

[Daniel-Svensson]

[danneesset@2013-11-03]
It looks like the EntitySets already have an internal dictionary for looking up entities which should provide usable.

EntitySet currently have a method " internal Entity GetEntityByKey(object[] keyValues)" which can be used to retreive an entity given it's key. Internally all entitites seems to be stored by key in a variable called "_identityCache".

It should be quite easy to use this functionallity for foreign key relationships, but I think it would also be of use if there was a public API for this.

[Daniel-Svensson]

For the scenario of childen having to find their parent there is an old draft of a solution in https://github.com/Daniel-Svensson/OpenRiaServices/tree/feature/entity_ref

The code generation must probably be updated to use the entity ref