Answer / ravin

Unique constraint and unique index are different things but
their goals might be similar.

Unique index is created implicitly with the creation of
Primary key and unique key both.
Hence no primary key can be created without a unique index.

Answer / smita

Hi,
No , we cant create pk eithout unique index it
implicitelygenerater by oracle.
I want to clear that pk can b on one or more col but only
one pk.
While unique constraint can b one or more col and can b one
or morn unique key in a table

Answer / deepak singh

No,
B'cas when you create d primary key then orcale
automatically created unique index

Answer / nisith ranjan samal

Yes,you can create primary key without creating unique index.
Alter table table_name add constraint constraint_name primary key(colum_name) disable

Answer / suneel

yes

Answer / prashant

Primary key = Unique Index + Not NUll Constraint .

So we can create primary key without Unique index ..But it
is created as combination of both (Unique Index + Not NUll
Constraint ) in oracle databases.

We need not have to create Unique index . :)

Answer / anil kumar jampana

YES WE CAN CREATE. FIRST CREATE NON UNIQUE INDEX THEN
CREATE PRIMARY KEY.

Answer / sowmya k

Yes we can create a primary key without creating the Unique
key. The primary key concept is same similar to the unique
key. We can set primary key to only one column, but a
unique key constraint can be set to more then one column.

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