Objectspaces is an O/R Mapping component that will be integrated into whidbey.
For details, see:
Http://msdn.microsoft.com/library/default.asp? Url =/library/en-US/dnadonet/html/objectspaces. asp
Currently, only SQL Server 2000 & SQL Server Yukon is supported for the objectspaces of the release.
During query execution, objectspaces uses the query string called opath and also supports the span parameter to specify whether to cascade to return a set of sub-objects of an object:
"SpanIs a comma-separated string that identifies related objects that will be returned by the query. specifying a span value of "orders" ensures thatOrderObjects related to anyCustomerObject are returned by the query as well. All orders are automatically packed into the orders property ."
To improve performance and reduce memory usage, objectspaces uses the delay loading technology when loading sub-object sets. That is, it will not be loaded from the database until the object is actually used in the code.
"To improve performance and memory use in parent/child relationships, objectspaces provides a facility known"Delay Loading". It works both for one-to-least and one-to-one relationships. the idea is that child objects are loaded in memory and on demand only at the time that they are requested."
I have probably read the article. It may be because of the first look. I feel that the data structure in the example is still relatively simple and the function is not very powerful, it is insufficient to describe objects with complex structures (with nested tree structures. However, Microsoft should not be disappointed. The true colors of the O/R Mapping Framework will be known only after the release is released :)