Re: btree on disk

On Oct 21, 9:56 pm, gordonb.2c...@xxxxxxxxxxx (Gordon Burditt) wrote:
For learning purposes, i want to implement a btree on disk on an unix
system(freebsd). I am aware of the existence of dbm/ndbm. But this
doesn't solve my purpose.

What purpose? Just learning, or did you have a specific application
in mind?

I understand the necessity of a temporary
file for write/update purposes.

It is not absolutely necessary to use a temporary file to make
changes in databases that are set up so you can do updates in place.

I would like to know in-detail and in-
depth how this could be achieved(use of cache/shared memroy,etc.). I

A database on disk file can be done on disk. Explicit use of cache
is not necessary (the filesystem is likely to provide it, wanted
or not). Use of shared memory isn't necessary if you have nothing
to share it with. You didn't say anything about multiple programs
trying to update the database at the same time.



would like to know the concepts,tricks and hints with respect to this.
Also, pls let me know if there are books which clearly explain how a
database is implemented, probably with sample code in c/c++ explaining
the use of shared memory, merging of files after updates etc.- Hide quoted text -

- Show quoted text -

Hi,

Thanks for replying to my post. I appreciate it.

I have a definite application in mind. The application is nothing but
a web-server/web service. Since i know unix,c,sockets,data structures,
i wanted to write one of my own, at my free time. I felt this would be
the optimal way to learn the nuances.

yes, there would be multiple processes that access the same data.
hence looking out for a book/this group for further directions.

Thanks,
Balaji.

.

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