What is a clustering index ?

Answer Posted / mainframe.rahulz

A DB2 index is a clustering index if the CLUSTER keyword is
specified when the index is created.In a clustered index
rows are stored continuously in a an
order.

When you define a clustering index on a DB2 table, you
direct DB2 to insert rows into the table in the order of the
clustering key values. The first index that you define on
the table serves implicitly as the clustering index unless
you explicitly specify CLUSTER when you create or alter
another index. For example, if you first define a unique
index on |the EMPID column of the EMP table, DB2 inserts
rows into the EMP table in the order of the EMPLOYEE ID
unless you explicitly define another index to be the
clustering index

Eg:CREATE INDEX Index name
ON tablename CLUSTER;

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