What are the disallowed characters for a VARCHAR2 in Oracle?
I have a dropdown list, which populates by querying a column called USERS.

I had a problem where the dropdown would not populate when one of the records had a `$` symbol in it. 

But, now I queried the columns, and there are no $symbols. What other characters are disallowed, similar to $? I wasn't able to find a comprehensive list anywhere.
What are the disallowed characters for a VARCHAR2 in Oracle?
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I have a dropdown list, which populates by querying a column called USERS.

I had a problem where the dropdown would not populate when one of the records had a `$` symbol in it. 

But, now I queried the columns, and there are no $symbols. What other characters are disallowed, similar to $? I wasn't able to find a comprehensive list anywhere.