If Sunday then show Week rest else present in oracle reports

Hi dear I am working in oracle reports I have a column ATT_DATE which have dates for the month next column I have :Day which I create function like this which gives me day

begin
  RETURN TO_CHAR(:ATT_DATE, 'DAY');
end;

It gives me Day of the Date which present in :ATT_DATE Now I wants to make one more function which checks SUNDAY then gives me two these things like if Sunday than Weekly Rest else Present in :Status column I write this code

function M_DAY2Formula return CHAR is
begin
  IF TO_CHAR(:ATT_DATE, 'DAY') = 'SUNDAY' THEN
     RETURN 'WEEK REST';
  ELSE
     RETURN 'PRESENT';
  END IF;
end;

but it neve Takes Sunday it gives in all days Present

Solution

I believe it is about TRIM. See the following example:

SQL> with dates as
  2    (select trunc(sysdate, 'iw') + level - 1 datum
  3     from dual
  4     connect by level <= 10
  5    )
  6  select datum,
  7         to_char(datum, 'DAY') dan,
  8         to_char(datum, 'DAY', 'nls_date_language = english') dan2,
  9         --
 10         length(to_char(datum, 'DAY', 'nls_date_language = english')) len_dan2,
 11         --
 12         case when to_char(datum, 'DAY', 'nls_date_language = english') = 'SUNDAY' then 'Week rest'
 13              else 'Present'
 14         end status,
 15         --
 16         case when trim(to_char(datum, 'DAY', 'nls_date_language = english')) = 'SUNDAY' then 'Week rest'
 17              else 'Present'
 18         end status2
 19  from dates
 20  order by datum;

DATUM      DAN         DAN2        LEN_DAN2 STATUS    STATUS2
---------- ----------- --------- ---------- --------- ---------
15.02.2021 PONEDJELJAK MONDAY             9 Present   Present
16.02.2021 UTORAK      TUESDAY            9 Present   Present
17.02.2021 SRIJEDA     WEDNESDAY          9 Present   Present
18.02.2021 ČETVRTAK    THURSDAY           9 Present   Present
19.02.2021 PETAK       FRIDAY             9 Present   Present
20.02.2021 SUBOTA      SATURDAY           9 Present   Present
21.02.2021 NEDJELJA    SUNDAY             9 Present   Week rest
22.02.2021 PONEDJELJAK MONDAY             9 Present   Present
23.02.2021 UTORAK      TUESDAY            9 Present   Present
24.02.2021 SRIJEDA     WEDNESDAY          9 Present   Present

10 rows selected.

SQL>

In other words:

if your date language isn't English, you can't compare it to "SUNDAY" (that's dan in my example)
if there's nothing wrong with the language, why the first case (the status column) doesn't work properly? Because of the length - see? No matter which day it it, length is 9 in all cases.
therefore, trim the DAY value and then it works as expected

Or, in Reports Builder:

function M_DAY2Formula return CHAR is
begin
  IF trim(TO_CHAR(:ATT_DATE, 'DAY')) = 'SUNDAY' THEN     --> TRIM, here
     RETURN 'WEEK REST';
  ELSE
     RETURN 'PRESENT';
  END IF;
end;