Lecture 2
From Compsci1
Columns and data types –
-In the example in access we can see that we can restrict the data in the column to characters that make sense for the data type.
- -Text - Text or combinations of text and numbers, such as addresses. Also numbers that do not require calculations, such as phone numbers, part numbers, or postal codes.
- -Memo - Lengthy text and numbers, such as notes or descriptions. Up to 64,000 characters
- -Number - Numeric data to be used for mathematical calculations, except calculations involving money (use Currency type). Set the FieldSize property to define the specific Number type.
- -Date/Time
- -Currency - Currency values. Use the Currency data type to prevent rounding off during calculations. Accurate to 15 digits to the left of the decimal point and 4 digits to the right.
- -AutoNumber - Unique sequential (incrementing by 1) or random numbers automatically inserted when a record is added.
- -Tables – are the primary unit of storage in the relational model. Each row represents one occurrence of the entity that the table represents, and each column represents one attribute for that entity. Show design view.
--mickdemp 16:58, 19 October 2006 (EDT)
