| title | sys.dm_column_store_object_pool (Transact-SQL) | Microsoft Docs | |
|---|---|---|
| ms.custom | ||
| ms.date | 03/17/2017 | |
| ms.prod | sql | |
| ms.prod_service | database-engine, sql-database | |
| ms.reviewer | ||
| ms.technology | system-objects | |
| ms.topic | language-reference | |
| dev_langs |
|
|
| ms.assetid | a8a58ca7-0a7d-4786-bfd9-e8894bd345dd | |
| author | stevestein | |
| ms.author | sstein | |
| manager | craigg | |
| monikerRange | =azuresqldb-current||>=sql-server-2016||=sqlallproducts-allversions||>=sql-server-linux-2017||=azuresqldb-mi-current |
[!INCLUDEtsql-appliesto-ss2016-asdb-xxxx-xxx-md]
Returns counts of different types of object memory pool usage for columnstore index objects.
| Column name | Data type | Description |
|---|---|---|
database_id |
int |
ID of the database. This is unique within an instance of a SQL Server database or an Azure SQL database server. |
object_id |
int |
ID of the object. The object is one of the object_types. |
index_id |
int |
ID of the columnstore index. |
partition_number |
bigint |
1-based partition number within the index or heap. Every table or view has at least one partition. |
column_id |
int |
ID of the columnstore column. This is NULL for DELETE_BITMAP. |
row_group_id |
int |
ID of the rowgroup. |
object_type |
smallint |
1 = COLUMN_SEGMENT 2 = COLUMN_SEGMENT_PRIMARY_DICTIONARY 3 = COLUMN_SEGMENT_SECONDARY_DICTIONARY 4 = COLUMN_SEGMENT_BULKINSERT_DICTIONARY 5 = COLUMN_SEGMENT_DELETE_BITMAP |
object_type_desc |
nvarchar(60) |
COLUMN_SEGMENT – A column segment. object_id is the segment ID. A segment stores all the values for one column within one rowgroup. For example, if a table has 10 columns, there are 10 column segments per rowgroup. COLUMN_SEGMENT_PRIMARY_DICTIONARY – A global dictionary that contains lookup information for all of the column segments in the table. COLUMN_SEGMENT_SECONDARY_DICTIONARY - A local dictionary associated with one column. COLUMN_SEGMENT_BULKINSERT_DICTIONARY – Another representation of the global dictionary. This provides an inverse look up of value to dictionary_id. Used for creating compressed segments as part of Tuple Mover or Bulk Load. COLUMN_SEGMENT_DELETE_BITMAP – A bitmap that tracks segment deletes. There is one delete bitmap per partition. |
access_count |
int |
Number of read or write accesses to this object. |
memory_used_in_bytes |
bigint |
Memory used by this object in the object pool. |
object_load_time |
datetime |
Clock-time for when object_id was brought into the object pool. |
On [!INCLUDEssNoVersion_md], requires VIEW SERVER STATE permission.
On [!INCLUDEssSDS_md], requires the VIEW DATABASE STATE permission in the database.
Index Related Dynamic Management Views and Functions (Transact-SQL)
sys.dm_db_index_physical_stats (Transact-SQL)
sys.dm_db_index_operational_stats (Transact-SQL)
sys.indexes (Transact-SQL)
sys.objects (Transact-SQL)
Monitor and Tune for Performance