rtrim ( string_expression )

return string_expression

The RTrim function removes all whitespace characters from the right end of a string.
LTrim trims the left end of the string and Trim removes all whitespace characters from both the beginning and ending of a string

Whitespace means the ASCII characters chr(9) - Horizontal Tab, chr(10) - Newline, chr(11) - Vertical Tab, chr(12) - Formfeed, chr(13) - Carriage Return, ' ' - Space, and many others characetrs from UNICODE like: chr(0xA0) - No-break space, chr(0x2009) - Thin Space, and others.