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sys.dm_db_missing_index_groups

Returns information about what missing indexes are contained in a specific missing index group.

Column name Data type Description

index_group_handle

int

Identifies a missing index group.

index_handle

int

Identifies a missing index that belongs to the group specified by index_group_handle.

In SQL Server 2005, an index group contains only one index.

Remarks

Information returned by sys.dm_db_missing_index_groups is updated when a query is optimized by the query optimizer, and is not persisted. Missing index information is kept only until SQL Server is restarted. Database administrators should periodically make backup copies of the missing index information if they want to keep it after server recycling.

Neither column of the output result set is a key, but together they form an index key.

For information about enabling and disabling missing index information collection, see About the Missing Indexes Feature.

For information about limitations of this feature, see Limitations for Using the Missing Indexes Feature.

For information about transaction consistency in relation to the missing indexes dynamic management objects, see About the Missing Indexes Feature.

Permissions

To query this dynamic management view, users must be granted the VIEW SERVER STATE permission or any permission that implies the VIEW SERVER STATE permission.

See Also

Reference

sys.dm_db_missing_index_columns
sys.dm_db_missing_index_details
sys.dm_db_missing_index_group_stats

Other Resources

About the Missing Indexes Feature

Help and Information

Getting SQL Server 2005 Assistance

Change History

Release History

17 July 2006

Changed content:
  • Clarified that a group contains only one index in the definition of index_handle.