Most people realize the importance of a functional database to businesses and individuals. But, design mistakes and flaws are common, even for the experienced developer. For someone with little or no experience, mistakes are bound to happen.
Everything starts with good planning. You know what some of your data storage needs are. But, what will they be like in the future? Failing to think about future needs is one of the common mistakes and often results in the need for reprogramming.
There is no way to plan for everything, of course. Life is full of surprises. But, with a cooperative effort between experts in your field of choice and experts at database design, it is possible to accurately determine your requirements, now and in the future.
Requirements analysis is a separate skill that some designers have and others don't. When you are shopping for a designer, don't be afraid to ask about their requirements analysis skills. If they stare blankly or hesitate, then you might want to politely excuse yourself.
Along with failing to plan for the future, another common mistake is not using SQL (Structured Query Language) facilities to protect the data integrity. SQL is used to dictate base rules that will never change. Outlining and building these rules into the initial database design will prevent future problems.
For example, if a business owner frequently allows employees to discount prices that have been stored in the database, there is probably a maximum allowable discount. If an employee tried to exceed the maximum, the change would not be allowed, if the rule had been written into the original program.
The design company or professional that you choose should be able to help you better understand all of these things. There are a number of different program developers in this field. Most of them charge by the hour, but some freelancers charge on a per project basis.
Your costs can be as low as $600 for an MS Access database converted from a provider's own spreadsheet. That price does not include analysis, testing or training. Basically, it's a grid that you will fill in on your own.
Other costs could include hardware, software and software licenses. A design professional should be able to outline all costs ahead of time. It is not unusual for complex projects to cost more than $10,000. There is no typical or average fee, so it pays to shop around. Just be sure to deal with someone that is experienced in database design and you'll be safe.