On Friday 14. May 2010 10.42.17 Trinath Somanchi wrote:
> Hi All,
[snipped]
> This way the data in the table is tree structured. Also A single
> manufacturer has all mode of vehicles. I'm in my way to design this DB for
> use in PgSQL. But for a vast data, data retrieval is a very costly task
> (Joining all tables).
>
> Can any one guide me of this design, on how the structure looks like. Hard
> about Inheritance feature of pgSQL. But not aware of how implementation
> goes.
You should think about a more normalized structure. Think about a table of
"manufacturers", and a table of "models", the latter with a foreign key
referencing the id of the former. The number of wheels is obviously an
attribute of "models".
regards,
--
Leif Biberg Kristensen
http://solumslekt.org/blog/