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Table Alias and Dual Table

470436Oct 1 2010 — edited Oct 1 2010
Dear Oracle Gurus,

I know that Dual Table is a 1 row one column table
Select * from Dual will display 1 row with X as the value

but how Select sysdate from dual brings the System date

or Select 5*6 from dual performs those calculations

Purely for knowledge updation purpose how these things are possible

Select <column name> from < table name >

means select the data from the column of the table

Where as Select sysdate from dual .... sysdate is not a field name in the dual table , it has a field called dummy !

Secondly
The table alias is just a alternative name or does it has anything more than that like Dual ?

With Warm regards
ssr
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Locked on Oct 29 2010
Added on Oct 1 2010
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