In addition to heap tables, starting from GPDB 7, AO/CO tables can also be clustered. Motivation CLUSTER, in general, ensures that the blocks of a table are physically ordered by the column(s) belonging to a supplied index. It has a direct benefit for tables which loaded in an
Introduction We are introducing a capability to alter the storage characteristics of an already populated table with the ALTER TABLE command in GPDB 7. This means that users can now go from a heap table to an AO or AOCO table (or any manner of combinations of the
Introduction Unique constraints are a classic relational database feature that ensures uniqueness of a column or a group of columns at data ingress time or at index build time. They can be specified with the UNIQUE / PRIMARY KEY keywords. Unique indexes are the entities that power them.