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More on Data Types

posted Oct 23, 2011, 4:06 PM by Eddie Woo
Last time we introduced the idea of a data dictionary, which describes the fields. We'll now have a closer look at the different characteristics that fields in a database can take on.
  1. Describe the six main numerical data types, with reference to their unique characteristics.
  2. Explain (with examples) why numbers will occasionally be represented with the text/char data type instead.

    The following questions relate to the data below, which represents example data from the "renter" table in a real estate agent's database.

  3. Construct a data dictionary to describe the data stored in the table.
  4. Justify your choice of data types and storage sizes.
  5. Calculate the approximate storage required if the table contains 1000 records.
Renter Code
Telephone Number
Postcode
Rent
Occupation Date
Under Lease
458703
9123 4567
2056$230.00
3/12/2005Y
594223
9567 4321
2057$395.004/3/1999N
934882
02 46322345
2570$410.5831/10/2001N
239922
4589 7654
2690$195.004/3/2006Y
345533
4322 8933
2856$240.0016/7/2006Y

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