Is primary key = unique key,not null?
If yes,please explain
IF No,please explain
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Answer Posted / arti kesharwani
No they are not equal because
we can have more than one column with not null+Unique constraints but we can have only one primary key in the table.
e.g
we can not create a table like this
create table test(id number primary key , name varchar2(10) primary key)
but we can create
create table test(id number unique not null , name varchar2(10) unique not null)
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