1. M3 - Estimating the size of a database

2. Estimating space needed
Estimating space needed is particularly important if the database is very large.
The forms, reports, and queries will all be added to the data, making a total of several hundred KB.

3. Depending on the database software you use, you may well be able to estimate the size of your database. This is an example of a hotel database estimation.
Booking ID
AutoCounter [4 bytes]
Customer_Name
Text of 20 characters
[20 bytes]
Telephone _Number
Room_Number
Number [4 bytes]
Check_in_date
Date [stored as text – dd/mm/yyyy is 8 bytes
Check_out_date
Maximum record size
64 bytes

4. Taking this a little further if you know that you were going to store 1,000 records we would be able to calculate that our database would have a size of 64,000 bytes.
If the database grew to 10,000 records, we would be storing 640,000 bytes.

5. Activity
Calculate how much storage does the data in your mobile phone database need?

6. overhead Some databases have what is called an overhead .
This is where additional memory is used to store information about the objects as well as the data stored in the tables.
Such as logo used in the reports, or the design of the query.
These overheads are more difficult to calculate.