Book Image

Getting Started with CockroachDB

By : Kishen Das Kondabagilu Rajanna
Book Image

Getting Started with CockroachDB

By: Kishen Das Kondabagilu Rajanna

Overview of this book

Getting Started with CockroachDB will introduce you to the inner workings of CockroachDB and help you to understand how it provides faster access to distributed data through a SQL interface. The book will also uncover how you can use the database to provide solutions where the data is highly available. Starting with CockroachDB's installation, setup, and configuration, this SQL book will familiarize you with the database architecture and database design principles. You'll then discover several options that CockroachDB provides to store multiple copies of your data to ensure fast data access. The book covers the internals of CockroachDB, how to deploy and manage it on the cloud, performance tuning to get the best out of CockroachDB, and how to scale data across continents and serve it locally. In addition to this, you'll get to grips with fault tolerance and auto-rebalancing, how indexes work, and the CockroachDB Admin UI. The book will guide you in building scalable cloud services on top of CockroachDB, covering administrative and security aspects and tips for troubleshooting, performance enhancements, and a brief guideline on migrating from traditional databases. By the end of this book, you'll have gained sufficient knowledge to manage your data on CockroachDB and interact with it from your application layer.
Table of Contents (17 chapters)
1
Section 1: Getting to Know CockroachDB
4
Section 2: Exploring the Important Features of CockroachDB
9
Section 3: Working with CockroachDB
Appendix: Bibliography and Additional Resources

DQL

DQL is used for reading or querying data or table metadata. SQL statements involving SELECT and SHOW fall under this category.

SELECT is a very commonly used SQL syntax to read table data. It takes the following parameters:

  • ALL: Doesn't eliminate duplicate rows.
  • DISTINCT: Eliminates duplicate rows.
  • DISTINCT ON ( a_expression): Eliminates duplicate rows based on a scalar expression.
  • target_element: A scalar expression to determine a column in each result row, or to retrieve all columns in case of an asterisk (*).
  • table_expression: A table expression from which the data has to be retrieved.
  • AS OF SYSTEM TIME  timestamp: Retrieves data as it existed at the time of this timestamp, where timestamp refers to a specific time in the past. This can return historical data, which can be stale.
  • WHERE a_expression: Only retrieves rows that return TRUE for a_expression.
  • GROUP BY a_expression: Groups results on one or more columns.
  • ...