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Archive for May 30th, 2007

Google’s StreetSide

Posted by decipherinfosys on May 30, 2007

Yesterday, Google launched it’s street-view mapping feature in an attempt to further create a richer experience for it’s geoweb services. They have partnered with Immersive Media and Greg Sadetsky has blogged about the technology behind this work. Google is not the only company that is striving for this space – Microsoft has a bird’s eye view as well in it’s maps with a large coverage thanks to their relationship with Pictometry. Another company that is in the fray is the EveryScape as they attempt to provide a 3-D Web available to the users.  They have a demo on their site that you can drive through to get a feel for it.  Interesting concept.

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Yet Another Potential Acquisition

Posted by decipherinfosys on May 30, 2007

Looks like ebay is all set to acquire StumbleUpon (a social bookmarking discovery service) at the close of business today for close to $75 million. This seems like a weird acquisition but the hypothesis given by Om Malik does seem to make sense – you can read more on that in his blog post – here.

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Views and Synonyms

Posted by decipherinfosys on May 30, 2007

Synonyms have existed in Oracle since long – however, they are pretty new to SQL Server world as this feature was introduced in SQL Server 2005.  One of the common questions asked is what is the difference between the two…here are a couple of those:

  • A view is created on one or more objects (tables, views, functions) and can include more than one object type as well as more than one object (example: 3-4 tables, 1 function, 1 view can be combined together to form a single view – a logical definition).  Synonyms are created on only one single object – a table, a view, a function, a stored procedure etc.
  • Not all views are updateable by definition.  If a view is a single table view, it would be updateable, however, if it is comprised of complex calculations and joins, it is not directly updateable – one has to write Instead Of triggers (IO triggers) in order to make them updateable.  Synonyms (when created on tables or single table views) are updateable since they are created on a single object.
  • An index can be created on a view thus forming an indexed view (SQL Server) or a materialized view (Oracle) which materializes the data to the disk – this is pretty common in data warehousing and BI applications.  Synonyms are just a logical definition.
  • Synonyms (in Oracle) can be created as a public or a private synonym.  For a view, one needs to specifically grant privileges since there is no such thing like a public or a private view.

Both views and synonyms can be created over a db-link (Oracle) or linked servers (SQL Server) and are very commonly used for enforcing a security layer in the schema.

Posted in Oracle, SQL Server | 1 Comment »