Oracle BI Answers - bins and column selector
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I'm new to Oracle BI Answers and have a quick question - 

I have a created a report which has a column selector, allowing the user to select between age range, gender, etc. 

Having spoken with the user, he wanted to group together a couple of categories in gender category that logically fit together ('unspecified' and 'unknown').

I edited the formula and created a bin to group these two categories together. However, now when i choose the column selector, all of my dropdown options bring back the gender category (age range, etc etc). Gender is also duplicated, so that there are two options on my dropdown.

I've noticed this in a couple of other reports I have tried as well. Any idea why this is happening and is there a simple way of fixing it?

Please let me know if you need any further info :)

Thanks
Alex