using variable name in order by

Hi,
Is there a limitation whereby I can't substitute the variable (varname) with literal string such such name or sal in the ORDER BY clause below? I can use variable in the WHERE clause but not in the ORDER BY.

OPEN emprefcursor FOR
select name from emp where sal>10000 order by varname;

Based on certain conditions, the varname can be name or sal. However, for some reasons, when I ran the procedure, it failed to replace the varname. Any other alternatives to accomplish the same thing?

Thanks.

Geraldine

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