/*****
    function: bool_to_string: boolean -> varchar2
    purpose: expects a boolean, and returns an equivalent
        string version (for top-level SQL*Plus use...!)

    examples: bool_to_string(TRUE) = 'TRUE'
              bool_to_string(FALSE) = 'FALSE'
*****/

create or replace function bool_to_string(bool_val boolean)
                           return varchar2 as
begin
    if bool_val then
        return 'TRUE';
    else
        return 'FALSE';
    end if;
end;
/
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