New Trace flags for better maintenance of deleted rows in Columnstore Index

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Qualification Limit for REORGANIZE to remove deleted rows from a rowgroup in Columnstore Index:

By default when one runs ALTER INDEX REORGANIZE the qualifying limit to remove delete rows from a rowgroup is –> the specific rowgroup have 10% of the max possible rows in a rowgroup deleted.

 

As the max possible rows in a row group is 1M rows, the qualification limit is that we need to have 100K rows deleted in a row group for the Reorganize to remove them from the Rowgroup.

 

From <https://docs.microsoft.com/en-us/sql/relational-databases/indexes/reorganize-and-rebuild-indexes?view=sql-server-ver15#defragmenting-indexes-by-rebuilding-or-reorganizing-the-index>

 

This threshold limit has few concerns

 

for few