Databases-tools and techniques

Databases-tools and techniques

1. Table Characteristics

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

2. Validation

   • to check for errors
   • applies to a range
   • correct format
     • post code
     • input mask
   • correct field size
   • correct data size
   • Examples
     • format Check
       • Checks the data is in the right format
     • 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
     • Lookup table
       • Looks up acceptable values in a table
     • 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
     • manually
     • External source
       • Spredsheet
   • Edit
   • Delete

4. Indexing

   • Primary key
   • foreign key

5. Relationships