scalability in Database

[kri shan]

What is scalability in Database ?

[Paul Sturrock]

scalability

n : the quality of being scalable.

How well a solution to some problem will work when the size of
the problem increases.

For example, a central server of some kind with ten
clients may perform adequately but with a thousand clients
it might fail to meet response time requirements. In this
case, the average response time probably scales linearly with
the number of clients, we say it has a complexity of O(N)
("order N") but there are problems with other complexities.
E.g. if we want N nodes in a network to be able to communicate
with each other, we could connect each one to a central
exchange, requiring O(N) wires or we could provide a direct
connection between each pair, requiring O(N^2) wires (the
exact number or formula is not usually so important as the
highest power of N involved).

[Jeanne Boyarsky]

Paul,
Where did that definition come from?

[Paul Sturrock]

I just lazily chucked the word in dictionary.com.

[Jeanne Boyarsky]

Oh. (You may want to credit them next time)

[Stefan Wagner]

On a database, my first ideas are:
- number of rows in a table
- number of tables in the database
- number of simultanous users

An other question might be, whether a change in the hardware (bigger/ faster drives, faster network hardware, more and faster RAM, more and faster CPU(s) clustering, ...) will lead to nearly equivalent effects in the usability of the DB - faster responses, more data/ users might be managed accordingly, ...