Kexi/Handbook/Introduction to Databases/Database Design
Database design needs careful planning. Note that Contacts table redesign proposed in section 1.2 can generate problems when the table is filled with data. For example, renaming a field is a simple task, but splitting the Address field into separate fields requires careful and tedious work.
To avoid such situations, rethink your database project before you create it in your computer, and before you and others will start to use it. Thus, by investing some time initially, you will most probably save your time on everyday use.