November 2012
Beginner
320 pages
6h 42m
English
As we have seen, some systems may store data in a denormalized form and, in the previous section, we saw how we could normalize the data. In essence, we were turning the data from column into a row. However, with some data, we may wish to change its normalized form not to rows, but to individual columns. For example, suppose a system stores its employee data with the following schema:
[employee_id] | [name]
And the name field holds the first name and last name of the employee in the following format:
[last_name], [first_name]
An example file is shown as follows:

Note that the schema does not have three fields, but that ...
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