Fluent.Interface


Oslo and new declarative language ‘D’ to be unvelied at Microsoft’s PDC 2008

The PDC postponed in 2007 will give people plenty to talk about in October.

I am particularly looking forward to the unveiling of Oslo, and getting my hands on the CTP.  I have been a Domain Driven Design advocate for a while now, and believe it is import to have a good vision for the model and how it is mapped back to implementation.  Oslo is all about modeling and is set to include:

  1. a ‘tool’ for so the BA types can visualise the problem domain
  2. a new domain specific language ‘D’ for mapping the model down to SQL.
  3. a (SQL) repository for storing the above

Microsoft has done a good job making most of .NET framework core libraries flexible and extensible, so let’s hope this will be a better offering then the Entity Framework V1, which was very limiting.  I still use NHibernate and see no reason to switch camps until they improve the design.

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Microsoft’s cloud computing offering with SDDS

Microsoft weighs in with its cloud computing offering in the form of SQL Server Data Services.  Currently in beta, users are able to sign up for free access.

A good screen cast walks you through the new tiered ‘ACE’ architecture which is designed around a top level ‘Authority’ a unit of geo-location which maps to an explicit DNS address eg:

brightsparc.data.beta.mssds.com

Under this Authority are Containers, and within a container is a series of Entities.  The flat structure is analogous to Tables and Rows, however a Row can represent different Kinds of data that doesn’t necessarily conform to the same schema. In fact any data other then the core ID, Version and Kind attributes are ‘Flexible Properties’ and set similar to a key based dictionary.

Under the hood this functionality could well be implemented with the new Filtered Index and Sparse Column features of SQL 2008 which allow for efficient storage of such data.

SSDS is a web service accessed over the wire using a SOAP or simple REST interface currently secured with basic credentials over https.  To get started I recommend downloading the SDK to create / update and query your data using the explorer GUI.  In REST speak, use POST to create a record, PUT to update and record and DELETE speaks for itself.  Moving forward cloud computing security is a challenge for Microsoft, but will no doubt tie in with it’s claim-based Card Space initiative.

Ryan Dun has a great blog with some examples of what is possible right now with SSDS, as well as very nifty open source REST library that can wrap POCO’s for persisting them to the cloud.

Although I did experience some unexpected outage on the service, Microsoft do plan to charge for this service in the future so I’m sure they will be looking at SLA of at least two 9’s if they are planning on competing with the likes of Amazon and Google.