SQL Server, Columnstore object
Applies to: 
SQL Server
The SQLServer:Columnstore object provides counters to monitor columnstore index execution in Microsoft SQL Server.
The following table describes the SQL Server Columnstore counters.
| Columnstore counters | Description |
|---|---|
| Delta Rowgroups Closed | Number of delta rowgroups closed. |
| Delta Rowgroups Compressed | Number of delta rowgroups compressed. |
| Delta Rowgroups Created | Number of delta rowgroups created. |
| Segment Cache Hit Ratio | Percentage of column segments that were found in the columnstore pool without having to incur a read from disk. |
| Segment Cache Hit Ratio Base | For internal use only. |
| Segment Reads/Sec | Number of physical segment reads issued. |
| Total Delete Buffers Migrated | Number of times tuple mover has cleaned up the delete buffer. |
| Total Merge Policy Evaluations | Number of times the merge policy for columnstore was evaluated. |
| Total Rowgroups Compressed | Total number of rowgroups compressed. |
| Total Rowgroups Fit For Merge | Number of source rowgroups fit for MERGE since the start of SQL Server. |
| Total Rowgroups Merge Compressed | Number of compressed target rowgroups created with MERGE since the start of SQL Server. |
| Total Source Rowgroups Merged | Number of source rowgroups merged since the start of SQL Server. |
Example
You begin to explore the query performance counters in this object using this T-SQL query on the sys.dm_os_performance_counters dynamic management view:
SELECT * FROM sys.dm_os_performance_counters
WHERE object_name LIKE '%Columnstore%';