In Oracle, there is no function available to convert boolean to string (varchar2). You will have to use IF, CASE, or DECODE statement.

The following is a PL/SQL program to convert boolean to varchar2 string:

Example

declare
  b_var boolean := true;
  v_var varchar2(10) := case when b_var then 'true' else 'false' end;
begin
  dbms_output.put_line(v_var);
end;

Output:

true
Statement processed.
0.01 seconds