index fragmentation

SQL Server Typical Maintenance Plans: Automatic Statistics Update

Some time ago, we reviewed the automation of index defrag. Now, it is time to look at statistics.

First of all, what do we need statistics for?

During execution of any query, query optimizer is trying to build an optimal execution plan (within the limits of available information). The plan constitutes the operations sequence, by means of which you can get the result described in the query.

While selecting one or another operation, the query optimizer considers statistics, that describes value distribution for columns within a table or index, as one of the most significant input data resources.

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SQL Server Index Fragmentation In-depth

There is no way to avoid index fragmentation in any SQL Server environment. It does not depend on your SQL Server version or I/O subsystem you have, or your hardware. In this article, we will drill down into SQL Server index fragmentation issue. We will figure out why index fragmentation is a problem and how it affect on overall performance, discuss how to detect and avoid it. (more…)

SQL Server Typical Maintenance Plans – Part 1: Automated Index Defragmentation

It’s incorrect to consider a database as a stable unit, since various kinds of undesirable situations can appear over time — database performance degradation, malfunctions, etc.

To minimize occurrence of such situations, maintenance plans are created, that guarantee stability and optimal performance of any databases.

Among maintenance plan tasks, the following can be pointed out:

  1. Index defragmentation
  2. Statistics update
  3. Backup and checking the logical and physical integrity of all the objects in database

Let’s consider automation of each task. (more…)