Database Sizing?

[Prabhu_9]

Hi,

We are in process of creating datamodel. We need to provide initial and forecast (after month, 6 month , 1 year) for Database Size. Can someone let me know how to forecast the same ? for now we have modelled 25 tables.

Thanks

[A. Clay Stephenson]

If a chicken and a half can lay an egg and a half in ... how long does it take?

There is no way to answer your question without much more data.

The way this is typically done is to enter (either manually or automatically) some amount of typical data (a day's worth, a month's worth, ...) and then extrapolate. Do you expect the data to grow linearly as a function of time? Exponentially? Logarithmically? Are there certain periods when the growth is expected to significantly deviate from the norm? If the data are heavily indexed especially with composite indices, the indices can vastly exceed the actual data
in size. You also need to determine if the data will continue to grow without end or will you reach some equilibrium where old data are deleted and/or archived?

You have a lot more homework to do before you can even begin to ask the right questions --- much less the answers.

One other potential "gotcha" to avoid if automatically creating data is to enter the data in a very ordered fashion. This can sometimes trigger very skewed index tree growth.

[Jov]

Know the size of the tables you're modelling, then make so best guess assumptions in terms of growth. Ball park figures and better on the worst case side.

In fact, if you have access to the designer of the application, then they should more or less know what to expect, or at least provide some idea of the storage projection based or requirements etc.


Jov

[Prabhu_9]

thanks. guess i framed the question wrong.

i wanted a general idea what are the areas we need to concentrate to comeup with approx database size reqs.

your reply did list down some of them. Let me start collecting those info. if there are more in the list please let me know.

Thanks a lot.