Databases-tools and techniques

Databases-tools and techniques

1. table charactersistics

   • columns=feilds
   • row=records
   • rows and colums
   • field types
     • Boolean/logical
       • yes/no
       • true/false
       • web
         • hyperlink
   • althabetic
     • text
     • memo
     • numeric
       • dates
       • time
       • currency
       • numbers

2. check for errors

   • apply for range
     • correct format
       • correct filed size
         • correct data type
       • postcode
         • validation
           • example
             • lookup table
               • Looks up acceptable values in a table
             • check digit
               • The last one or two digits in a code are used to check the other digits are correct
             • length check
               • Checks the data isn't too short or too long
             • format check
               • Checks the data is in the right format
             • presence check
               • Checks that data has been entered into a field
             • range check
               • Checks that a value falls within the specified range
             • spell check
               • Looks up words in a dictionary

3. records

   • add
   • edit
   • manually
   • external source
   • delete
   • spread sheet

4. relationships

   • one to many
   • one to one
   • many to many

5. indexing

   • primary key
   • foreign key