Specifies columns whose values are used as limits for
partitioning the index across multiple storage areas. You cannot
name columns not specified as index key segments.
If the index key is multisegmented, you can include some or all
the columns that are joined to form the index key. You must
specify the columns in the order in which they were specified
when the index key was defined. If you only include a subset
of the columns, you must include the leading segments of the
multisegmented index.
For example, if a CREATE INDEX statement specifies a
multisegmented index based on the columns LAST_NAME, FIRST_NAME,
and MIDDLE_INITIAL, then the USING clause must include the first
segment LAST_NAME, or the first two segments, LAST_NAME, and
FIRST_NAME, or all the segments of the index. This is true for
sorted indices only.
The database system uses the values of the columns specified in
the STORE USING clause as a key to determine in which storage
area an index entry associated with a new table row belongs.
There is no restriction for hashed scattered indexes. For hashed
ordered indexes, all segments listed, except the last segment
can be included. Also, HASHED ORDERED indexes have further
restrictions on the data type of the final column; it must be
a date/time or integer numeric data type.