SDR queries all associations even if they are not in the requested projection [DATAREST-1089]

Josh Wand opened DATAREST-1089 and commented

I have noticed that even when specifying a lightweight projection, SDR nonetheless queries every single association on my entity, without checking to see if it's in the projection. This results in many extra DB queries that are dramatically slowing down my application.

I've traced the code to this line:

https://github.com/spring-projects/spring-data-rest/blob/master/spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/EmbeddedResourcesAssembler.java#L77

There are checks to see if the association is linkable, or if itself has an excerpt projection, but not to see if the requested association is specified in the projection itself.

Can this check be added? This is a major performance issue.

(see also https://stackoverflow.com/questions/44379069/how-to-avoid-n1-queries-with-spring-data-rest-projections )

3 votes, 5 watchers