Re: Data structure for indexing on multiple keys.

Shankar wrote:
>
> I have fair knowledge of B-tree and hash indexing mechanisms.
> What data structure/algorithms should I read upon if I want to
> create indexes on multiple keys of a same relation? For e.g if
> a Employee relation has EmpNo, EmpName, EmpSalary, EmpDepth
> attributes & users can query on any of these attributes. Do I
> create separate B-trees for each key?
>
> Please note that this is not about composite keys but supporting
> multiple keys for searching. Thanks in advance for inputs!

The answer has to depend on the use you make of the resulting database. For example, do you want to search it for all with an EmpSalary between certain limits, and treat that as a reduced database for other operations? Or do you simply want to access the data associated with a particular key. Does the database need to be dynamically modified. And so forth.

-- 
"I'm a war president.  I make decisions here in the Oval Office
 in foreign policy matters with war on my mind." -         Bush.
"If I knew then what I know today, I would still have invaded
 Iraq. It was the right decision" -       G.W. Bush, 2004-08-02