all, I wonder if providing the size of the database MDF file and with amount of the data in the database currently, i mean for number of years worth data existing in the system in estimating the disk size, is it a ok to estimate it like that. Manager is insisting on estimating the size this way, what other factors should we consider. I want list out the things that need to be aware of, which could make us differ from the original estimation?
That assumes a fixed growth rate, and if that is acceptable, then it can be used. Can you extrapolate a growth rate from the existing data? eg. if the total database size is now 12GB after 3 years, but you can see that 2008 has 3GB data, 2009 has 4GB, and 2010 has 5GB, then you can factor in a growth of 1GB per year too. so instead of saying 12GB = 3 years, therefore for the next 5 years we need (12/3)*5 = 20GB you would need 6 + 7 + 8 + 9 + 10 = 40GB Whatever method you choose, aim to revisit the calculation ater 6 months/ 1 year/ etc to see if the growth is as expected. I know you want to estimate the disk size now, but I'd rather know sooner than later that I am going to exceed the capacity, instead of waiting for the day to come.
Hi Katie, In addition to what Kev said I would like to add that a big item that has come back to kill any growth estimates for me has been new development projects and business growth. A lot of people don't understand that the database may not grow at the same rate that your customer base does(Customer Base is often a easy point of measurement). When I do capacity planning, I try to add in comparative numbers. Something that will give decision makers the ability to help them measure. For example: 100 Customers with a 10% a year growth customers has proven to show a 10% amount of growth over the last 18 months. I hope that helps without adding a bunch of lose ends.