Well-designed queries are critical for SQL Server database performance. Inefficient queries can create overly-complex algorithms that use excessive resources and slow performance overall. Optimizing queries can have an outsized impact on processing speed, resource usage, and more. SQL Server query tuning best practices are relatively simple, and mostly rely on the use of proper syntax:

● Use SELECT over SELECT* column list
● Use EXISTS in place of COUNT()
● Avoid SQL DISTINCT if possible
● Avoid IN-operator clause
● Use wildcards correctly
● And more.

SQL Diagnostic Manager gives DBAs visibility into overall query efficiency, ensuring query execution plans are adhering to best practices — and giving DBAs the opportunity to quickly address the issue if not.

With Query Monitor, DBAs can establish criteria for the queries and subqueries they wish to capture, and then filter those results by metrics to analyze the queries in a given category. This allows DBAs to quickly and easily pinpoint and address slow-running queries as part of their regular performance tuning process.

Monitoring and analyzing SQL query performance enables DBAs to troubleshoot potential performance issues well before they cause serious problems. With SQL Diagnostic Manager, DBAs can analyze SQL query performance in several ways:

● Signature Mode View, which displays general performance information for individual SQL statements or query signatures
● Statement Mode View, which shows specific performance information for individual SQL statements or query signatures
● Query History View, which shows the daily historical performance impact of a query
● Query Waits View, which displays waits over time and by duration to pinpoint top bottlenecks

When slow-running or otherwise inefficient queries have been identified, DBAs can apply proven optimization techniques to improve overall database performance. Generally speaking, a large number of slow-running queries indicates poor performance, which needs to be addressed.