Being a master of OpenOffice Databases, you decided to use the database to narrow your search for the criminal. Rich's house, you began putting the clues together.
Rich's house and the chief knew that it would take your talents to solve the mystery. A burglary had just been committed at Mrs. The chief ordered you back to the station. You had just gotten to sleep when the phone roused you back to the real world. Mystery 1: It was a dark and stormy night. You will then use the same Database to Solve the Second Mystery. Read Mystery Number 1 below, then follow the directions for completing a query below. You will now generate queries in order to determine who the actual thief is. What's a query? A query is a way to get specific information from the database. This can make sure that all new entries, regardless of who did it, must follow the rules of your database.Once you have entered all your data click the "save" icon on the Title Bar to save your table. If it’s essential that a record contain a certain field (in our example, and employee MUST have an ID number) make sure to set Entry Required to True for that field, as in the screenshot above. If you chose the fields from the dropdown menus in the wizard, these types should be automatically applied to the right fields. A number like EmployeeID makes sense as an integer, and text fields like first and last name should be text (CHAR or VARCHAR). On the second page of the Table Design wizard, you specify what type of data will go into that field. There’s (probably) no chance of two employees having the same ID number, so it makes a perfect primary key. That may sound confusing, but it typically just means that you need a column like EmployeeID, and each entry has a different, unique number. In short, this means that tables should generally have a column where each row in that column is unique on that table. Secondly, it’s important for tables to have a primary key. If you find yourself putting anything into a table that does not match with the title of that table (like Employee or Billing), it probably belongs in a different table. For starters, each table should represent only one idea – ie the Employee table should not contain shipping information. Database design is far too large a subject to cover here in detail, so we’ll just mention a few basics and leave some links at the bottom of this page for more detail.
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