Mon. Nov 18th, 2019

Sequelize v5.21 released, Node.js ORM

1 min read

When you start building web applications and APIs you often need something that interacts with databases for you. Maintaining relationships between tables, fetching related records and managing transactions gets very repetitive over time when using just raw queries. Sequelize abstracts these tasks away for you and provides you with a database layer.

It provides simple access to  MySQL, MariaDB, SQLite and  PostgreSQL databases by mapping database entries to objects or object-to-database entries. In short, ORM (Object-Relational-Mapper). It is written entirely in JavaScript and is suitable for the environment of Node.js.

It has been under development since July 2010 and is used by a large number of users. It’s under active development with new features introduced relatively often.



  • Schema definition
  • Schema synchronization/dropping
  • 1:1, 1:M & N:M Associations
  • Through models
  • Promises
  • Hooks/callbacks/lifecycle events
  • Prefetching/association including
  • Transactions
  • Migrations
  • CLI (sequelize-cli)

Sequelize v5.21 has been released. The update change as follows:

Bug Fixes

  • postgres: update upsert regex to match the last RETURNING * (#11538) (2b9baa2)


  • mariadb: support indexHints on mariadb dialect (#11573) (a34399f)