- single or bulk row inserts
- create or insert (with append hint) as select from another table
- conventional and direct path loads
Many DBAs do not know the fastest method, and instead use proprietary DB export/import tools that do not serve heterogeneous data warehouse architectures.
However, the fastest method for bulk loading DBs like Oracle is through a bulk load pre-sort:
CoSort can also transform and report on the data (so the DB does not have to). Having tables in query order, and removing bulk transformation overhead from the DB layer, both improve query performance.