Just a quick trick today. I discovered this quite early on in my Tableau journey and it made me feel like a wiz, despite being only a small formatting change.
When you have a distinct field on the columns shelf Tableau displays these values across the bottom of the view in the conventional x-axis position.
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But if you wanted to have them across the top for some design reason, perhaps to draw more attention to them then follow these steps:
Go to Analysis > Table Layout > Advanced as shown:
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Which opens this window:
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Uncheck the highlighted box and the labels will appear at the top of the view like so:
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As the name of the check box suggests this works on charts with a vertical axis and is particularly useful for categorical data.
I like this trick as it imbues the user with more control over how their charts look and that's always a good thing - though it is a bit tucked away so I thought I'd share for anyone who might make use of it.