Add or modify a primary index or primary AMP index. You cannot modify basic table parameters or revalidate a table or join index in the same ALTER TABLE statement that includes MODIFY options.
- index_name
- Name for an unnamed primary index or a change to the name of a primary index. For information about naming database objects, see Teradata Vantage™ - SQL Fundamentals, B035-1141.
- (index_column_name)
- Change the properties of the primary index for table. For a composite primary index, index_column_name indicates a comma-separated list of all the index columns in parenthesis. You cannot specify the begin or end columns of a derived period column in a primary index. The table must be empty.
- AMP
- Rows are hash-distributed to AMPs for a column-partitioned table or join index. Column partition values are ordered on each AMP by an internal partition number and a row hash for a column-partitioned table or join index.
- INDEX
- If a PRIMARY INDEX clause and a PARTITION BY clause are specified, a column-partitioning level may be included in the PARTITION BY clause. The PARTITION BY clause can be included in the PRIMARY INDEX specification or by itself in the index list. The PARTITION BY clause can include row-partitioning levels.
- NOT NAMED
- Drop the name of a named index.
- UNIQUE
- Change a nonunique primary index to a unique primary index. The table must be empty.
- NOT UNIQUE
- Change a unique primary index to a nonunique primary index. The table must be empty.