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Rows_sampled: It gives the total number of sample rows for the statistics.

Rows: It shows the total number of rows at the time of the last statistics update.

Last_updated: It is the date and time of the last statistics update.

Stats_ID: It is the unique ID of the statistics object.

object_id = OBJECT_ID ( 'HumanResources.Employee' ) We can use DMV sys.dm_db_stats_properties to view the properties of statistics for a specified object in the current database.Įxecute the following query to check the statistics for HumanResources.Employee table. It opens the statistics properties and shows the statistics columns and last update date for the particular statistics.Ĭlick on the Details, and it shows the distribution of values and the frequency of each distinct value occurrence (histogram) for the specified object.

Right-click on the statistics and go to properties.

We can get details about any particular statistics as well. Expand the object ( for example, HumanResources.Employee), and we can view all available statistics under the STATISTICS tab. We can view SQL Server statistics for an existing object using both SSMS and the T-SQL method.Ĭonnect to a SQL Server instance in SSMS and expand the particular database. We might also face blocking, deadlocks that eventually causes trouble to the underlying queries, resources.

Improper statistics might mislead query optimizer to choose costly operators such as index scan over index seek and it might cause high CPU, memory and IO issues in SQL Server. The query optimizer should be updated regularly. These statistics provide distribution of column values to the query optimizer, and it helps SQL Server to estimate the number of rows (also known as cardinality). SQL Server statistics are essential for the query optimizer to prepare an optimized and cost-effective execution plan. This article gives a walk-through of SQL Server Statistics and different methods to perform SQL Server Update Statistics.