Update statistics in sql 2005

This is measure from some rowmodctr. This has the effect that big tables with a monotonously growing key where queries goes against the trunk have their statistics updated far too rarely.

Whereas small tables where all rows are updated frequently, or where or rows are added and deleted, have their stats updated very often, which may cause recompilation issues. This can take a long time some situations so it's sometimes better to do this manually. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more.

Ask Question. Asked 11 years, 1 month ago. Active 8 years, 11 months ago. Viewed times. The documentation states: A statistics update is initiated whenever the statistics used in a query execution plan fail a test for current statistics. Improve this question. Jacob Jacob 15 4 4 bronze badges. I bet you wish you were using SQL2K8 so you could change that index to a filtered index.

Add a comment. Active Oldest Votes. All one needs to know is the data distribution. In the second query, the filter criteria where clause is included — and this is on an indexed column which has unique sets of values. You can see the changes in the execution plan behavior specifically the change in the join operator from nested loops to a merge join with the different stats available now.

One can then look into creation of covered index or a change of clustered index etc. However, the physical records in the tables and the indexes will remain as is.

It is important to remember that the usage of these commands will let you see what kind of query plan changes will occur if the data volume changes — however, when you actually run those queries, those queries will complete very fast when run against empty or small data volume tables.

One can make use of these execution plans to analyze and look at how the estimated query plan and the cost is changing as the data volume changes.

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You can use our customized Search Engine based on Google's Co-op to narrow down your searches and get focussed results. You can see how the plan has changed for both the queries post these updates. Query 1: The plan drastically changed from a clustered index seek operation and an index scan operation to a clustered index scan and an index scan operator with parallelism and hash match kicking in. Query 2: In the second query, the filter criteria where clause is included — and this is on an indexed column which has unique sets of values.

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