客戶要求將一個view改回原來的樣子（即，不適用與新需求）。由於上次的修改採用了新增計算列的方法，所以，只需要將檢視中的統計指標改回原來的列即可，修改起來挺方便的。

試想，如果未採用新增計算列的方法，而是通過Information Link修改了基本資料，那這次改動就沒這麼容易了。

可見，計算列功能還是具有很大的靈活性的。

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Calculated Column

A column that has been created from different expressions where calculations on other columns could be included. TIBCO Spotfire supports two different types of expressions: Insert Calculated Column, which creates a new column in the data table, and Custom Expression, which is used to dynamically modify the expression used on an axis or to define a setting. Both types of expressions are created with a similar user interface.