Whether you're creating an address file with a simple file manager or retrieving data from a full-blown relational database-management system, you can save yourself a great deal of time and grief if you follow a few commonsense rules:
1. Choose the right tool for the job.
2. Think about how you'll get the information out before you put it in.
3. Start with a plan, and be prepared to change your plan.
4. Make your data consistent.
5. Databases are only as good as their data is.
6. Query with care.
7. If at first you don't succeed, try another approach.
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