Hi All,

I am new to both this blog and technology. I was able to
see a response for one of the questions on triggers as
below.

I would like to know why are we using
" if rtrim(to_char(sysdate,'day'))=rtrim('sunday') then"
instead, can't we use
" if sysdate = 'sunday' then".

I can understand the use of "rtrim", but dont know y v r
using to_char. I have seen this in many cases but did not
get a convincible explaination.

Please help me with this and do excuse if this question
sounds silly.

Thanks in advance......

create or replace trigger trg_sun
before insert on <table name>
begin
if rtrim(to_char(sysdate,'day'))=rtrim('sunday') then
raise_application_error(-20345,'no transaction in sunday');
end if;
end trg_sun;

Answer Posted / eshwer

Hi,

see the below example you can easily understand that why we are using trim.

select decode(TRIM(to_char(SYSDATE,'Day')),'Monday','3','1') from dual


1. select decode(to_char(SYSDATE,'Day'),'Monday','3','1') from dual
Ans : 1 – error because eroju Monday ne kabatti query 3 return cheyali kani 1 return chesthundi. Karanam spaces so we need to use trim function.enduko kinda points chudu

2. Run this query and check the output select to_char(SYSDATE,'Day') from dual
3. select length(to_char(SYSDATE,'Day')) from dual  –- ee query run chei output 9 vasthundi. But Monday actual length is 6.


run these queries

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