In my blog entries "Teradata Columnar" and "9.2 Quintillion? What's that all about?", I discussed column partitioning and the increased partition limit that are introduced in TD 14.0.  But there are other TD 14.0 partitioning enhancements that you may find useful.  The following provides a brief introduction to these enhancements; for more detailed information, see the Orange Book: Increased Partition Limit and other Partitioning Enhancements, the Orange Book: Teradata Columnar, and the TD 14.0 manuals.

With row partitioning (for a PPI or column-partitioned table), the Teradata Database makes sure rows are placed in their appropriate partitions.  When the row partitioning for the table is altered, rows may need to move from one partition to another so they are in their appropriate partitions according to the altered partitioning.  The partitioning expression must be deterministic (always computes the same value for the same value of the partitioning column) to properly place and retrieve the row.

For instance if the table has RANGE_N partitioning, ALTER TABLE will move rows automatically from NO RANGE to newly-added ranges as needed.  Also, if a range is dropped, rows from that partition are moved to the NO RANGE, NO RANGE OR UNKNOWN partition or a newly-added range that covers the dropped range.

I was recently asked about NO RANGE, UNKNOWN, and NO RANGE OR UNKNOWN partitions for the RANGE_N function.  While these have been available since TD V2R5.0, there is sometimes confusion about what they mean and when to use or not use them.