Tag: Database Index
What Are the Types of Indexes in a Relational Database?
Using database indexes is one of the easiest ways to improve the overall performance of a database, more specifically query performance, if you select the right type. Knowing the types of indexes in SQL is very important since different indexes provide different benefits. We review commonly used indexes from the most popular RDBMS and explain when to use them.
What Are Database Indexes? A database index is an additional data structure created on top of the data in a table.
What Is a Database Index, and What Does It Do?
Understand what a database index does and how it can improve SQL query performance.
Modern databases store terabytes or petabytes of data and are a key resource for organizational operations and decision-making. A database index is a special data structure that allows quick access to specific pieces of information without having to read all data stored in a particular table. They ensure database performance in transactional environments.
How Does a Database Index Enhance Access to Information?
Tip #4 – How to Make a Column Unique
Sometimes there are columns in a table that don’t belong to primary key, but are still unique. To mark them as a unique, you have to create an alternate (unique) key containing it.
Single-column alternate (unique) key Select the table with the column you want to make a unique. Then, click the Alternate (unique) key tab in the Table properties panel on the right:
Click Add key:
What Is a Database Index?
Sooner or later there comes a moment when database performance is no longer satisfactory. One of the very first things you should turn to when that happens is database indexing. This article will give you a general overview on what indexes are without digging into too much detail. We’ll discuss additional database index topics in future articles.
In general, a database index is a data structure used to improve queries execution time.
SQL Performance Explained – the must-read book
Some time ago, the Vertabelo Team participated in the PostgreSQL Conference Europe 2013. Some of the talks were really nice. One of them stuck in my head for quite a long time. It was Markus Winand’s lecture titled “Indexes: The neglected performance all-rounder.” Although I had had a solid background in databases, this 50 minutes long talk showed me that not everything concerning indexes was as clear to me as I had thought.
