Book Image

Supercharging Node.js Applications with Sequelize

By : Daniel Durante
4 (1)
Book Image

Supercharging Node.js Applications with Sequelize

4 (1)
By: Daniel Durante

Overview of this book

Continuous changes in business requirements can make it difficult for programmers to organize business logic into database models, which turns out to be an expensive operation as changes to the database may result in errors and incongruity within applications. Supercharging Node.js Applications with Sequelize helps you get to grips with Sequelize, a reliable ORM that enables you to alleviate these issues in your database and applications. With Sequelize, you'll no longer need to store information in flat files or memory. This book takes a hands-on approach to implementation and associated methodologies for your database that will have you up and running in no time. You'll learn how to configure Sequelize for your Node.js application properly, develop a better sense of understanding of how this ORM works, and find out how to manage your database from Node.js using Sequelize. Finally, you'll be able to use Sequelize as the database driver for building your application from scratch. By the end of this Node.js book, you'll be able to configure, build, store, retrieve, validate, and associate your data from a database to a Node.js application.
Table of Contents (16 chapters)
1
Part 1 – Installation, Configuration, and the Basics
4
Part 2 – Validating, Customizing, and Associating Your Data
10
Part 3 – Advanced Queries, Using Adapters, and Logging Queries

Isolation levels and advanced configuration

In this section, we will be covering the different isolation levels and configuration options available from Sequelize for every type of transaction. For managed transactions, the method signature looks like this: sequelize.transaction(options, callback). The unmanaged transaction signature is sequelize.transaction(options).

Here is a list of configurable options for both transaction types:

  • type—A SQLite option to set the transaction type. Possible values are DEFERRED (the default), IMMEDIATE, and EXCLUSIVE. Refer to https://www.sqlite.org/lang_transaction.html.
  • isolationLevel—Sets the transaction’s isolation level. The following explanations are under the context of MySQL but should be applicable to other database management systems (DBMS) with minute differences. There are four available levels for Sequelize, as outlined here:
    • READ_UNCOMMITTED—Reads data using non-locking mechanisms. This could...