bcp in works in one of two modes:
Fast bcp – logs each row insert that it makes, used for tables that have one or more indexes or triggers.
Slow bcp – logs only page allocations, copying data into tables without indexes or triggers at the fastest speed possible.
To determine the bcp mode that is best for your copying task, consider the:
Size of the table into which you are copying data
Amount of data that you are copying in
Number of indexes on the table
Amount of spare database device space that you have for re-creating indexes
Fast bcp might enhance performance;
however, slow bcp gives you greater data recoverability.
