Thanks for the kind words! And thanks for your question, as it gives me the opportunity to clarify what I clearly had not described clear enough.
Two methods of inserting data exist:
* Trickle load: Add rows to open delta store rowgroup, using row mode storage. (Will eventually be compressed into columnstore storage when the rowgroup is full, e.g. has 1,048,576 rows)
* Bulk load: Added in a new rowgroup that is immediately compressed into columnstore storage after the insert finishes.
Bulk load is used when the following conditions apply:
1: Insert has at least 102,400 rows; AND
2: Insert is done by either any of the tools that use the Bulk Insert API (as listed in the article), or done by an INSERT INTO ... SELECT ... statement.
Trickle insert is used when the following conditions apply:
1. Insert has 101,399 rows; OR
2: Insert is done through a tool that does not suport Bulk Insert API; OR
3: Rows are added by a MERGE instead of an INSERT statemment (regardless of number of rows); OR
4: Rows are added as new due to an UPDATE statement (see http://www.sqlservercentral.com/articles/Stairway+Series/136174/), also regardless of number of rows.
So the short answer to your question is: "102,400" :satisfied: