I have read a lot about using flattened structures in solr (instead of relational). Looks like it is preferable to use flattened structure. But in our case we have to consider using (sort of) relational structure to keep index maintenance cost low.
Does anyone have deeper insight into this? 1) When should we definitely use relational type of structure and use join? (instead of flattened structure) 2) When should we definitely use flattened structure (instead of relational)? 3) What are the signs that one has made a wrong choice of flattened vs relational? 4) Any best practices when relational structure and join is used? 5) I understand that parallel sql (in solr) will have more relational functionality support? Any ETA on when the parallel sql will support joins? Thanks for your help!
