Table of Contents

Class AzureSynapseAnalyticsSchema.NodesColumnStoreRowGroup

Namespace
LinqToDB.Tools.DataProvider.SqlServer.Schemas
Assembly
linq2db.Tools.dll

sys.pdw_nodes_column_store_row_groups (Transact-SQL)

Applies to: √ Azure Synapse Analytics √ Analytics Platform System (PDW)

Provides clustered columnstore index information on a per-segment basis to help the administrator make system management decisions in Azure Synapse Analytics. sys.pdw_nodes_column_store_row_groups has a column for the total number of rows physically stored (including those marked as deleted) and a column for the number of rows marked as deleted. Use sys.pdw_nodes_column_store_row_groups to determine which row groups have a high percentage of deleted rows and should be rebuilt.


See sys.pdw_nodes_column_store_row_groups.

[Table(Schema = "sys", Name = "pdw_nodes_column_store_row_groups", IsView = true)]
public class AzureSynapseAnalyticsSchema.NodesColumnStoreRowGroup
Inheritance
AzureSynapseAnalyticsSchema.NodesColumnStoreRowGroup
Inherited Members
Extension Methods

Properties

DeletedRows

deleted_rows NOT NULL bigint

Number of rows physically stored in the row group that are marked for deletion.

Always 0 for DELTA row groups. 
[Column("deleted_rows")]
[NotNull]
public long DeletedRows { get; set; }

Property Value

long

DeltaStoreHoBTID

delta_store_hobt_id NOT NULL bigint

The hobt_id for delta row groups, or NULL if the row group type is not delta. A delta row group is a read/write row group that is accepting new records. A delta row group has the OPEN status. A delta row group is still in rowstore format and has not been compressed to columnstore format. 
[Column("delta_store_hobt_id")]
[NotNull]
public long DeltaStoreHoBTID { get; set; }

Property Value

long

DistributionID

distribution_id NOT NULL int

Unique ID of the distribution. 
[Column("distribution_id")]
[NotNull]
public int DistributionID { get; set; }

Property Value

int

IndexID

index_id NOT NULL int

ID of the clustered columnstore index on *object_id* table. 
[Column("index_id")]
[NotNull]
public int IndexID { get; set; }

Property Value

int

Object

objects (sys.objects)

[Association(ThisKey = "ObjectID", OtherKey = "ObjectID", CanBeNull = false)]
public ObjectSchema.Object Object { get; set; }

Property Value

ObjectSchema.Object

ObjectID

object_id NOT NULL int

ID of the underlying table. This is the physical table on the Compute node, not the object_id for the logical table on the Control node. For example, object_id does not match with the object_id in sys.tables.

To join with sys.tables, use sys.pdw_index_mappings. 
[Column("object_id")]
[NotNull]
public int ObjectID { get; set; }

Property Value

int

PartitionNumber

partition_number NOT NULL int

ID of the table partition that holds row group *row_group_id*. You can use *partition_number* to join this DMV to sys.partitions. 
[Column("partition_number")]
[NotNull]
public int PartitionNumber { get; set; }

Property Value

int

PdwNodeID

pdw_node_id NOT NULL int

Unique ID of a Azure Synapse Analytics node. 
[Column("pdw_node_id")]
[NotNull]
public int PdwNodeID { get; set; }

Property Value

int

RowGroupID

row_group_id NOT NULL int

ID of this row group. This is unique within the partition. 
[Column("row_group_id")]
[NotNull]
public int RowGroupID { get; set; }

Property Value

int

SizeInBytes

size_in_bytes NOT NULL int

Combined size, in bytes, of all the pages in this row group. This size does not include the size required to store metadata or shared dictionaries. 
[Column("size_in_bytes")]
[NotNull]
public int SizeInBytes { get; set; }

Property Value

int

State

state NOT NULL tinyint

ID number associated with the state_description.

1 = OPEN

2 = CLOSED

3 = COMPRESSED 
[Column("state")]
[NotNull]
public byte State { get; set; }

Property Value

byte

StateDescription

state_description NOT NULL nvarchar(60)

Description of the persistent state of the row group:

OPEN - A read/write row group that is accepting new records. An open row group is still in rowstore format and has not been compressed to columnstore format.

CLOSED - A row group that has been filled, but not yet compressed by the tuple mover process.

COMPRESSED - A row group that has filled and compressed. 
[Column("state_description")]
[NotNull]
public string StateDescription { get; set; }

Property Value

string

TotalRows

total_rows NOT NULL bigint

Total rows physically stored in the row group. Some may have been deleted but they are still stored. The maximum number of rows in a row group is 1,048,576 (hexadecimal FFFFF). 
[Column("total_rows")]
[NotNull]
public long TotalRows { get; set; }

Property Value

long