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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