Re: Table DUAL

In article <8dahov$ruo$1_at_nnrp1.deja.com>,   icemelid_at_my-deja.com wrote:
>
>
> Hi Sir
>
> I know some simple uses of the DUAL table, like
>
> select 1+1 from dual
>
> Do you know some other uses about this table, if it
> is a table.
> Or could you tell me where to find some extra information.
>
> Thanks in advance.
>
>

The dual table can be used anywhere a one row table is necessary or useful such as in retriveing a function value into an appliation or for display in sqlplus:

The current Oracle user
select user from sys.dual;

The current date with or without time
select sysdate, to_char(sysdate,'MM/DD/YYYY HH24:MI:SS') from dual;

testing (or retrieving) column functions on a constant select my_func('test value') from dual;

Oracle internal operations also make use of the dual function.

--
Mark D. Powell  -- The only advice that counts is the advice that
 you follow so follow your own advice --


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