UNION Command Question

[informer30]

Hi All

I am new to oracle sql and wanted to know about the union command.

for example you have

select a.field1, a.field2, a.field3
from product a

union

select b.field1, b.field2, b.field3
from product1 b

The resultset is a distinct, i.e. I am correct in thinking all 3 fields have to be the same for the distinct record to show?

Many Thanks

 

[Turkbear]

Hi,
In the docs you were given links to in previous posts you will find that UNION removes duplicates and UNION All returns duplcates:

More info:

http://www.oracle-dba-online.com/sql/oracle_union_sorting.htm

To Paraphrase:"The Help you get is proportional to the Help you give.."

 

[Turkbear]

Hi,
It may have been someone else with a similar handle that got the links to the docs, so try this very good source for 10G:

http://www.oracle.com/pls/db102/homepage?remark=tahiti

or this one for all Oracle stuff:

http://tahiti.oracle.com

To Paraphrase:"The Help you get is proportional to the Help you give.."