Objects Within a Database

Objects Within a Database

1. Tables

   • Stores the data itself

2. Queries

   • Used to answer questions about the data. Can extract and display records which match certain criteria.
   • Queries answer questions about your data
   • Can be used to view, alter and analyse data from one or more tables in a database.
   • Can be used as the source of records in forms or reports
   • Only the required data is displayed
   • Can be saved for future use
   • Criteria
     • Wildcard symbols and maths operators can be used
       • Wildcards
         • * Matches any number of characters or none
         • ? Matches exactly one character
       • Maths Operators
         • _and_/_or_
         • >(Greater than)/<(Less than)
         • Between...and...(can be numbers or dates)
         • Criteria can be combined. E.g. >25 and <50

3. Reports

   • Used to format the output of data from tables or queries in a user friendly way - mainly for printing

4. Forms

   • Used to input and/or output data in a user friendly way - for on-screen use
   • Easily created using 'Wizards'
   • Forms can be used to both input and output data records
   • Allow records to be presented in a user friendly way
   • Text can be enhanced and additional text added
   • Allow command buttons to be added
   • Can be edited using a form editor
   • E.g. Send, Save, Delete
   • The best approach is to create a basic form using wizard and then modify it when it is needed
   • You can view data in a form. You can also add records, modify records and delete records
   • When you move off the record, the changes are made automatically to the table
   • Once you delete it is gone for good