Transforming data structure through pivots and unpivots
You can use pivot and unpivot transformations to change narrow tables into wide tables and vice versa. You can also use a pivot to permanently reduce the granularity of a data table by summing up to a higher level.
Take a look at the baseball player data. What sort of table do you think it is? It has columns for player name and team and then individual columns for a range of standard baseball statistics, with each statistic getting its own column. This was very convenient when we wanted to calculate the walk-to-strikeout ratio.
Unpivot
Let's see what happens when we unpivot the baseball player data table.
The data used here is BaseballPlayerData.xls
, which you can download from http://www.insidespotfire.com ...
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