When I try to do Max Rows , it still shows up the same. Please let me know if you would like me to post more information on this TiborK. The content you requested has been removed. Ask a question. Quick access.
Search related threads. Remove From My Forums. Asked by:. Archived Forums. This is the place for advice and discussions 2 4. Sign in to vote. Friday, August 9, PM. Saturday, August 10, AM. Hi I was think more along the lines for testing 1 Truncated my table.
Please rate your experience Yes No. Any additional feedback? In this article. Date and time the statistics were last updated. For more information, see the Remarks section in this page. Total number of rows in the table or indexed view when the statistics were last updated. If the statistics are filtered or correspond to a filtered index, the number of rows might be less than the number of rows in the table.
For more information, see Statistics. Total number of rows sampled for statistics calculations. Number of steps in the histogram. Each step spans a range of column values followed by an upper bound column value. The histogram steps are defined on the first key column in the statistics.
This Density value is not used by the Query Optimizer and is displayed for backward compatibility with versions before SQL Server String summary statistics are stored separately from the histogram and are created on the first key column of the statistics object when it is of type char , varchar , nchar , nvarchar , varchar max , nvarchar max , text , or ntext. Predicate for the subset of table rows included in the statistics object.
For more information about filtered predicates, see Create Filtered Indexes. For more information about filtered statistics, see Statistics. Total number of rows in the table before applying the filter expression. Persisted sample percentage used for statistic updates that do not explicitly specify a sampling percentage. You are commenting using your Google account. You are commenting using your Twitter account.
You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. Email Address:. Create a free website or blog at WordPress. Feeds: Posts Comments. Given below are both approaches.
Reference: MSDN. Using the output from one of the examples from above we can see that the output is divided into 3 sections. Note: For this histogram I have only shown the first 5 buckets to save space.
Just as there are two ways that statistics can be created, there are also a couple ways they can be updated, manually and automatically. Note: When statistics are updated, queries in the plan cache referencing these objects will recompile the next time they are called so you do have to be careful not to update statistics too often as the performance impact of frequently recompiling queries can hurt your overall system performance.
If this option is set SQL Server will check how many rows have been modified in the table and if a certain threshold is exceeded it will update the statistics and create a new execution plan for the plan cache. The rules for this threshold can be found in the SQL Server documentation and are as follows:. By default, with this option on, the statistics are updated synchronously.
That means that when SQL Server detects out of date statistics it will first update the statistics, generate a new execution plan, and then execute the query. With this option set your query will run with the currently cached query plan and the statistics will be updated in the background. Once the statistics update is complete the next query executed will generate and use a new query plan using the updated statistics. Determining whether statistics are out of date is a really difficult question to answer.
There are many different factors that can affect table, index or column statistics and cause them to generate poor performing query plans. You could have a table with many inserts, updates or deletes but depending on which values were affected it might not have much if any impact on the statistics. The opposite could also be true. If queries are only looking for new values e.
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