UNIQUE INDEX
Unique indexes guarantee that no two rows of a table have duplicate values in the columns that define the index.
Unique index is automatically created when primary key or unique constraint is created.
Ex: SQL> create unique index stud_ind on student(sno);
NON-UNIQUE INDEX
Non-Unique indexes do not impose the above restriction on the column values.
Ex: SQL> create index stud_ind on student(sno);
Unique indexes guarantee that no two rows of a table have duplicate values in the columns that define the index.
Unique index is automatically created when primary key or unique constraint is created.
Ex: SQL> create unique index stud_ind on student(sno);
NON-UNIQUE INDEX
Non-Unique indexes do not impose the above restriction on the column values.
Ex: SQL> create index stud_ind on student(sno);
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