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MS Xen might bridge the impedance mismatch

Check out one of the projects coming out of MS Research, Xen.  It's an attempt to integrate XML and SQL into an OOP language as first class objects.

There's a good summary article about it (with examples) by Robyn Peterson on ExtremeTech:
http://www.extremetech.com/article2/0,1558,1491790,00.asp

Still much too early to see whether this will help alleviate the impedance problem Joel mentions in today's post, but as a .NET programmer, I'm glad to see they're seriously thinking about it...

Gary Pupurs
Thursday, April 08, 2004


Check out the link that Joel provides at the beginning of the post.

Dan J
Thursday, April 08, 2004

The code samples look interesting, but I wonder how efficient it would be.

For example:

//Selecting all customers named Fred with a custid greater than 100
Customer* Freds =
      CustTable[it.name=="Fred" && it.custid>100];

This seems nice syntax (if you ignore the fact that it looks kile Freds might be a pointer to a Customer), but I wonder how it'd be implemented. If it is clever enough to build the appropriate SQL (select ... where name="Fred" and custid>100), then great.

On the other hand, if it simply fetches all the Customers, instantiates them, then iterates over them to see which ones satisfy the criteria, then this is not much good (especially if you have millions of Customers).

Steve Jones (UK)
Thursday, April 08, 2004

Doh, "kile" should be "like".

Steve Jones (UK)
Thursday, April 08, 2004

Maybe I'm reading too much into that code sample, but 'it.name=="Fred"' seems to imply that it's going to instantiate the Customer objects, otherwise it would have said 'it.name="Fred"'.

Steve Jones (UK)
Thursday, April 08, 2004

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