Creating a computed column
When you create a computed column, you write an expression, which is a statement that indicates how to calculate the data. In the report in Figure 3-1, each value in the Total column is calculated by multiplying the value in the QUANTITYORDERED field with the value in the PRICEEACH field.
Figure 3-2 shows the computed column, Total, using the following expression:
[QUANTITYORDERED] * [PRICEEACH]
When you refer to a data field in an expression, you must enclose the field name within brackets ([ ]). The field names are case-sensitive.
Figure 3-2  

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