22. 2. 2. When creating selector CASE statements, you cannot have NULL in the list of possible values.
Although the following code is correct from the syntax point of view, it doesn't work:
create or replace function f_getDateType (in_dt DATE) return VARCHAR2
is
v_out VARCHAR2(10); begin case TO_CHAR(in_dt,'d')
when null then
-- value will be null if in_dt is null
v_out:='<NULL>';
when 1 then
v_out:='SUNDAY';
when 7 then
v_out:='SATURDAY'; else
v_out:='WEEKDAY'; end case; return v_out; end;
/