Answer / vaibhavi_dixit

Dual table is know as magic table, which has only one
columns with name as "DUMMY" and a row with value X.
One can describe DUAL with desc dual; command.
It is mainly used for testing some math expressions or some
character functions like
select (2+2) from dual;
It is automatically created,assigned to SYS but accessible
to all users.

VD

Answer / santosh

Dual is a magic table

Answer / roopesh kumar

In oracle Dual is a magic table.

Answer / shekharjchandra

We can view the structure of the DUAL table by

SQL> DESCRIBE DUAL

or being in SYS user

SYS> SELECT DBMS_METADATA('TABLE','DUAL','SYS') FROM DUAL ;

Before that use below set command

SQL> SET PAGESIZE 100 -- or whatever you like so that you can see whole structure of the create table definition

Regards
J

Answer / annam.n

dual is an imaginary table.it only used for process any
functions on there, but we can't view the structure of the
dual table.so the dual table is a magic table

Answer / brahma

They are two tables in MS Sql Server
1.Delete table
2.Update table

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