Query Optimization in PostgreSQL. EXPLAIN Basics – Part 2

In my previous article, we started to describe the basics of the EXPLAIN command and analyzed what happens in PostgreSQL when executing a query.

I am going to continue writing about the basics of EXPLAIN in PostgreSQL. The information is a short review of Understanding EXPLAIN by Guillaume Lelarge. I highly recommend reading the original since some information is missed out.

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Troubleshooting long running queries in MS SQL Server

Preface

There is an information system that I administer. The system consists of the following components:

1. MS SQL Server database
2. Server application
3. Client applications

These information systems are installed on several objects. The information system is used actively 24 hours a day by 2 to 20 users at once on each object. Therefore, you cannot perform routine maintenance all at once. So, I have to «spread» SQL Server index defragmentation throughout the day, rather than defragmenting all the necessary fragmented indexes at one stroke. This applies to other operations as well.

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SQL Server In-Memory OLTP: The Basics

This is the first article in a series of articles about In-Memory OLTP. It helps you to understand how the new Hekaton engine works internally. We will focus on details of in-memory optimized tables and indexes. This is the entry-level article, which means you do not need to be an SQL Server expert, however, you do need to have some basic knowledge about the traditional SQL Server engine. Read More

Retrieving SQL Server Metadata with Help of T-SQL

This article contains a list of scripts that mine the SQL Server metadata in the various system functions, stored procedures, tables, and catalog views. Metadata queries are really helpful in discovering information for a given database schema. You can copy all the T-SQL scripts that are listed in this article and use for your own purposes. However, please do some tests before apply to a production database.

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