From the course: Microsoft Azure Database Administrator Associate (DP-300) Cert Prep by Microsoft Press

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Implement statistics maintenance tasks

Implement statistics maintenance tasks

From the course: Microsoft Azure Database Administrator Associate (DP-300) Cert Prep by Microsoft Press

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Implement statistics maintenance tasks

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- Welcome back. This is Lesson 9.2, Implement Statistics Maintenance Tasks. Before we get into configuring and implementing a statistics maintenance task, let's first review what statistics are. Let's begin with cardinality and defining what cardinality is. Query Optimizer determines the cost of executing a query based on a couple of key factors, one of which is the cardinality or total number of rows processed, the other being the uniqueness of data. So statistics then is the updating of the cardinality information because the query optimizer uses these statistics to estimate the cardinality or number of rows in the query result. So statistics for the query optimization are binary large objects, which contain the statistical information. The statistical information includes the distribution of values in one or more columns of a table or indexed rows. These are used to improve query performance. These statistics are then used by the query optimizer to generate a more accurate and…

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