Databases-Tools and Techniques

Databases-Tools and Techniques

1. Table Characteristics

   • Rows and Columns
     • Columns: Fields
     • Rows: Records
       • Add
         • Manually
         • External Source
           • Spreadsheet
       • Edit
       • Delete
   • Field types
     • Alphabetic
       • Text
       • Memo
     • Numeric
       • Numbers
       • Currency
       • Dates
       • Times
     • Boolean/Logical
       • Yes/No
       • True/False
     • Web
       • Hyperlinks

2. Validaton

   • To check for errors
   • Applies to range
   • Correct format
     • Postcode
       • Input mask
   • Correct field size
   • Correct data type
   • Examples
     • Check Digit
       • The last 1 or 2 digits in a code are used to check that the others are correct.
     • Format Check
       • Checks that the data is in the right format
     • Length Check
       • Checks that the data isn't too long or too short
     • Lookup Table
       • Lookup acceptable values in a table.
     • Presence Check
       • Checks that the data has been entered into a field
     • Range Check
       • Checks that the value falls in the right range
     • Spell Check
       • Looks up words in a dictionary

3. Indexing

   • Foreign Key
   • Primary Key

4. Relationships

   • One to many
   • Many to many
   • One to one