PL see the following I am not able to under stand

step1 --------------
select data_length from user_tab_columns where 
data_type='DATE';

DATA_LENGTH
-----------
7

step2 --------------

create table xyz
(a date);

Table created

step3 --------------

insert into xyz values (to_date('10-aug-03'))

1 row created

step4 --------------

SQL> select distinct(data_length) from user_tab_columns where 
2 data_type='DATE';

DATA_LENGTH
-----------
7

step5 --------------

create or replace view temp as (Select trunc(A) as a from xyz);

view created

step 6
SQL> select distinct(data_length) from user_tab_columns where
2 data_type='DATE';

DATA_LENGTH
-----------
7
8
step 7

select TABLE_NAME,COLUMN_NAME 
from user_tab_columns where
data_type='DATE' and data_length=8;


The data length for date column shows 8 when we use truc(date_column) in a view..
As oracle uses 7 bytes to store a date type
usage 
century year month date hour minute second

pls guide where has the length increased to 8..

when i use the dump function i see eight bytes of storage and in normal seven bytes of storage.. using excess-100 in case of century and year and using excess 1 in case of hour and minute..

Strange beahviour.. Only a master can help..

Regards,
Ashwani