Query Optimization

Optimize Your SQL by Reformulating the Spec

  • Article

As SQL developers, we tend to think of performance tuning in terms of crafting the best table indices, avoiding scalar and table valued functions, and analyzing query plans (among other things). But sometimes going back to the spec and applying some properties of elementary math can be the best way to begin to improve performance of SQL queries which implement mathematical formulas. This article is a case study of how I used this technique to optimize my SQL implementation of the Inverse Simpson Index.

5 (2)

2019-09-12

2,650 reads

The Query Optimizer: Date Correlation Optimisation

  • Article

In SQL Server 2005, a feature was introduced that was hardly noticed, but which might make a great difference to anyone doing queries involving temporal data. For anyone doing Data Warehousing, timetabling, or time-based pricing, this could speed up your queries considerably. Who better to introduce this than Query Optimizer expert, Fabiano Amorim?

2009-10-26

3,485 reads

Statistics Used by the Query Optimizer in Microsoft SQL Server 2008

  • Article

Microsoft SQL Server 2008 collects statistical information about indexes and column data stored in the database. These statistics are used by the SQL Server query optimizer to choose the most efficient plan for retrieving or updating data. This paper describes what data is collected, where it is stored, and which commands create, update, and delete statistics. By default, SQL Server 2008 also creates and updates statistics automatically, when such an operation is considered to be useful. This paper also outlines how these defaults can be changed on different levels (column, table, and database).

2009-07-24

2,506 reads

Blogs

Invest in Yourself Stop Making Excuses

By

Bob Pusateri (B|T) tweeted a quote image that really struck a chord with me...

Every Execution Plan Is An Estimated Plan

By

I consider myself to be the most responsible for making such a huge deal...

SQLSaturday Orlando Notes – Kahoot

By

The last two years we did Family Feud as part of our end of...

Read the latest Blogs

Forums

SQL Management studio 2014 express edition

By bokswager

Guys, Can I use SSMS 2014 Express edition to connect to a lower and...

unable access sql provider in powershell without running an invoke-sqlcmd first

By Steve T

I encountered a weird issue and hope that somebody may have a fix for...

Function to pad Bigint with leading zeros or other single characters

By Shane Clarke

Comments posted to this topic are about the item Function to pad Bigint with...

Visit the forum

Ask SSC

SQL Server Q&A from the SQLServerCentral community

Get answers