Comparing strings whilst ignoring some characters

Hi Everyone,

I have a common problem and whilst I can remember solving it in the past I'm drawing a mental blank this time...

I need to look for duplicates in a varchar2 field in a table. However I should ignore case, whitespace and non-alphanumeric characters. Obviously upper, rtrim and ltrim get me a long way to the solution, but... What is the easiest way to remove inline space, so that "the cat" equals "thecat". I thought I used the translate function, but a quick inspection didn't reveal how.

Thanks in advance,

          Mark.

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Author: Mark Richard
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