0 - 1 of 1 tags for oracleSQL

hi.
I want to know how to swap two values in a column in oracle sql table in a single query.
suppose I have a table emp which has a column job.
In job there are values 'CLERK' and 'SALESMAN' and others as well.
I want to swap 'SALESMAN' and 'CLERK'.
I did it with three queries.