5.   We listed 7 basic guidelines for when creating a table (e.g., •Choose Numeric data types ONLY if calculations are to be performed on the field

.). List 4 Other ones.

 

• Choose Numeric data types ONLY if calculations are to be performed on the field

 

• Make the lengths of the character columns long enough to accommodate future values (Remember the Y2K Problem)

 

• Apply the same guidelines for DECIMAL data as INTEGER data

 

• Don’t automatically choose VARCHAR over CHAR

 

• Use EXACTLY the same data types for columns which will be compared often or used in calculations together

 

 

• Use NOT NULL when a column MUST contain a value

 

 

• PRIMARY KEYS MUST always be NOT NULL