Difference between SELECT DISTINCT and SELECT UNIQUE [duplicate]

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Possible Duplicate:

Unique vs distinct multi-column in Oracle 9i

Proper difference between SELECT DISTINCT and SELECT UNIQUE with points and examples.

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SELECT DISTINCT and SELECT UNIQUE behave the same way in oracle.

While DISTINCT is ANSI SQL standard, UNIQUE is an Oracle specific statement.

Look here: http://psoug.org/definition/DISTINCT.htm

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Oracle official documentation

http://download.oracle.com/docs/cd/B28359_01/server.111/b28286/statements_10002.htm#sthref9346

States that:

DISTINCT | UNIQUE

Specify DISTINCT or UNIQUE if you want the database to return only one copy of each set of duplicate rows selected. These two keywords are synonymous. Duplicate rows are those with matching values for each expression in the select list.