Performance Tuning with SQL Server Dynamic Management Views

Chapter 5: Indexing Strategy and Maintenance
5.1, which returns some statistics from the dm_db_index_usage_stats DMV, and
joins to sys.indexes to get the index names.
SELECT DB_NAME(ddius.[database_id]) AS database_name ,
OBJECT_NAME(ddius.[object_id], DB_ID('AdventureWorks'))
AS [object_name] ,
asi.[name] AS index_name ,
ddius.user_seeks + ddius.user_scans + ddius.user_lookups AS user_reads
FROM sys.dm_db_index_usage_stats ddius
INNER JOIN AdventureWorks.sys.indexes asi
ON ddius.[object_id] = asi.[object_id]
AND ddius.index_id = asi.index_id ;
Listing 5.1: Querying index use in the AdventureWorks database.
The results are shown in Figure 5.1.
Figure 5.1: Results for indexes in the AdventureWorks database.
Firstly, you may notice the use of the OBJECT_NAME function to return the table/view
that owns the indexes retrieved from sys.dm_db_index_usage_stats. Note that
database_id is not an identified column in these system catalog views. This is because
these views reside in each database on the SQL Server instance, not within one of the
system databases (globally) across the instance. Therefore, we'll make use of a littleknown
feature of the OBJECT_NAME function which, in SQL 2005 and later editions,
accepts the database_id in the second parameter slot. In Listing 5.1, we could have
simply used:
OBJECT_NAME(ddius.[object_id], ddius.[database_id]) AS [object_name]
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