SQL returns subsets of all tables with only those tuples that would be part of the traditional (single-table) query result set
So it returns only the data that would be returned from the query, so the filtering is done.
I can see some uses of it. If you look at what something like Entity Framework does behind the scenes to return nested objects, you can see how something like this might help.
EF can have big problems with “Cartesian explosions” if an object has two lists of sub objects to return, it will get listA length x listB length items due to how the joins work. You can see how this leads to the explosion part of the name (with more objects or lists).
Their solution is a “split query” option, that does each sub table as a separate query, then seamlessly gives you the combined result.
If a change like this let’s you get those different table lists as distinct lists with the processing and round trip time of multiple requests then it could be a game changer.
So it returns only the data that would be returned from the query, so the filtering is done.
I can see some uses of it. If you look at what something like Entity Framework does behind the scenes to return nested objects, you can see how something like this might help.
Yeah, the post on Reddit had some insightful comments as well.
I did not think of nested objects that may be returned by an entity framework before.
EF can have big problems with “Cartesian explosions” if an object has two lists of sub objects to return, it will get listA length x listB length items due to how the joins work. You can see how this leads to the explosion part of the name (with more objects or lists).
Their solution is a “split query” option, that does each sub table as a separate query, then seamlessly gives you the combined result.
If a change like this let’s you get those different table lists as distinct lists with the processing and round trip time of multiple requests then it could be a game changer.
(Source - my last week 🤣😭 + lots of EF docs)