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Statistics are critical metadata used by SQL Server’s query optimizer, which influence the selected execution plan for a query.

The optimizer obtains its knowledge of the data, its distribution, and the number of rows a given query is likely to return from the available statistics.

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Database backups, integrity checks, and performance optimizations form the core of a DBA’s regular maintenance tasks.

Backups are usually at the top of the list, as data is one of the most important, if not most important, facets of a business.

My Question Is: When should we be Updating the Statistics, and why?

This seems like the kind of thing we should do less frequently than every day.

but if the statistics don't accurately reflect the current contents of the table you'll get a poorly-performing query.

How do you find out if statistics are correct, and what can you do if the automatic update of statistics isn't right for the way a table is used?this solution only rebuilds/reorganize and updates what is needed this way you might shortenthe time your maintinance plan takes and also save a hole lot of log space.. In your original post, you said that users are seeing a performance degredation due to this maintenance plan.Is there no other time to run this maintenance plan? I see that your plan encompasses index reorganization, when are you rebuilding indexes?allows the SQL Server query optimizer to produce good query plans consistently, while keeping development and administration costs low 2.Statistics are used by the query optimizer to estimate the selectivity of expressions, and thus the size of intermediate and final query results. Good statistics allow the optimizer to accurately assess the cost of different query plans and then choose a high-quality plan If you want to do update Statistics manually you should first know When Statistics are updated automatically If the SQL Server query optimizer requires statistics for a particular column in a table that has undergone substantial update activity since the last time the statistics were created or updated, SQL Server automatically updates the statistics by sampling the column values (by using auto update statistics).Of the 23 minute Maintenance Plan, Updating the Statistics takes a staggering 13 minutes.

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