Databases- Tools and Techniques

Databases- Tools and Techniques

1. Relationships

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

2. Table characteristics:

   • Rows and Columns
   • Columns = Fields
   • Rows = Records
   • Field types:
     • Alphabetic
       • Text
       • Memo
     • Numeric
       • Numbers
       • Currency
       • Dates
       • Times
     • Boolean/logical
       • Yes/No
       • True/false
     • Web
       • Hyperlink

3. Validation:

   • To check for errors
   • Applies to a range
   • Correct Format
     • Postcode
       • Input Mask
   • Correct field size
   • Correct data type
   • Check Digit
     • The last one or two digits in a code help identify if the other digits are correct.
   • Format Check
     • It checks whether the data is in the right format.
   • Length Check
     • To check whether the data is too long or too short.
   • Lookup Table
     • To look up acceptable values that are in the table.
   • Presence Check
     • To check whether the data has been entered into the correct field.
   • Range Check
     • Checks whether the value entered is in the correct range.
   • Spell Check
     • Looks up words in the dictionary.

4. Records

   • Add
     • Manually
     • External Source
       • Spreadsheet
   • Edit
   • Delete

5. Indexing

   • Primary Key
   • Foreign Key