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There are different ways you can view the details of the statistics objects.
For example, as shown in the query below, you can use the DBCC SHOW_STATISTICS command.
The next step is to copy this text, paste it into a query window in SQL Server Management Studio, then execute it against the instance.
Alternately you may choose only to execute it against select databases, but that is entirely up to you.
What we need is a quick solution for updating all the statistics for every database on our SQL Server instance. Because of this you simply can not rely on the engine to keep you statistics in check and current.
Before you go ahead and state the fact that you have AUTO_UPDATE_STATISTICS ON for your databases remember that does not mean that they are being updated! Here is a simple block of code that will iterate through all your databases in order to build the sp_updatestats command that can then be copied and pasted into a new query window for execution.
SQL Server Query Optimizer uses statistics to estimate the distribution of values in one or more columns of a table or index views, and the number of rows (called ) to create a high-quality query execution plan.
Often statistics are created on a single column but it’s not uncommon to create statistics on multiple columns.
Bad or missing statistics leads to poor choices by the optimizer: The result is horrific performance.
This command gives much better granularity of control: [cc lang=”sql”] — Update all statistics on a table UPDATE STATISTICS Sales.
Sales Order Detail — Update a specific index on a table UPDATE STATISTICS Sales.
Statistics refers to the statistical information about the distribution of values in one or more columns of a table or an index.
The SQL Server Query Optimizer uses this statistical information to estimate the cardinality, or number of rows, in the query result to be returned, which enables the SQL Server Query Optimizer to create a high-quality query execution plan.