Parameters are workbook variables that can replace a constant value in a sheet or dashboard. They can come in string, number or date format.
To create a parameter, click on the dropdown in the left pane and select Create Parameter.
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The parameter creation box will appear:
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Add a name for the parameter and specify the data type. In this case, I'm making a simple parameter that helps a user filter to different Regions in the Superstore dataset:
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Select a data type for the values it'll accept. I've chosen string because this parameter will have a list of locations.
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Specify a current value. This is the default value that this parameter will take. My current value is 'Central', a region in the superstore dataset.
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Select a value for when the workbook opens:
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Choose how the parameter accepts values - this can either be All, a List or a Range.
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You can add values from an existing fields. I'm adding the values from the Region field.
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Click okay and your parameter is ready to use.