Titlebook: SQL Server Query Performance Tuning; Grant Fritchey Book 20144th edition Sajal Dam and Grant Fritchey 2014

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Creating a Baseline, a number of Performance Monitor metrics for gathering data on these parts of the system. Within the descriptions of most of the counters, I referred to comparing your metric to a baseline. This chapter will cover how to gather your metrics so that you have that baseline for later comparison. I’ll g

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Query Performance Metrics,lyze the cause of a system bottleneck, it is important to examine the database application workload and identify the SQL queries causing the most stress on system resources. To do this, you can use Extended Events and other Management Studio tools.

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Index Analysis,of interesting interaction between indexes that you can take advantage of. There are also a number of settings that affect the behavior of indexes that I didn’t address in the preceding chapter. I’ll show you methods to squeeze even more performance out of your system.

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Database Engine Tuning Advisor, the existing indexes may not be entirely appropriate, and new indexes may be required. The task of deciding upon the correct indexes is complicated by the fact that an index change that benefits one set of queries may be detrimental to another set of queries.

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Statistics, Data Distribution, and Cardinality,oing to access data. The optimizer must have information about the data that defines an index or a column. That information is referred to as a .. Statistics define both the distribution of data and the uniqueness or selectivity of the data. Statistics are maintained both on indexes and on columns w

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Index Fragmentation,d) on a table, the cost of data retrieval is reduced by properly ordering the leaf pages of the index and the rows within the leaf pages. In an OLTP database, data changes continually, causing fragmentation of the indexes. As a result, the number of reads required to return the same number of rows i