Re: Indexes not allowed on (read-only) views: Why?

On Fri, Sep 16, 2011 at 4:47 PM, Stefan Keller <sfkeller(at)gmail(dot)com> wrote:
> A (read-only) view should behave like a table, right?
>
>> CREATE INDEX t1_idx ON t1 (rem);
> ERROR: »v1« not a table
> SQL state: 42809
>
> => Why should'nt it be possible to create indexes on views in PG?
>
> An index on a view can speed up access to the tuples underlying. And
> "indexed views" could be a method of storing the result set of the
> view in the database, thereby reducing the overhead of dynamically
> building the result set. An "indexed view" should automatically adapt
> modifications made to the data in the base tables. So, there is some
> overhead here, but this is ok when speed in retrieving results
> outweighs the cost...
>
> And there is no practical reason since SQL Server can do it! See
> "Creating Indexes on Views"
> http://msdn.microsoft.com/en-us/library/aa933124%28v=sql.80%29.aspx

implementation across databases is different. in postgres, views are
essentially macros, thus there is no data to index.

merlin