Typeorm Array Is Not Supported In Postgres

If you have been working with TypeORM and Postgres, you might have encountered the issue where TypeORM arrays are not supported in Postgres by default. Don't worry, though; there are ways to work around this limitation and still use arrays effectively in your database schema.

TypeORM is a popular Object-Relational Mapping (ORM) library for TypeScript and JavaScript. It provides a powerful set of tools for working with databases, including support for various database systems such as MySQL, PostgreSQL, SQLite, and more. However, when it comes to working with arrays in Postgres, you may run into some challenges due to the differences in how arrays are handled in different databases.

By default, when you try to define an array column in your TypeORM entity and use Postgres as your database, you may encounter an error indicating that arrays are not supported. This is because Postgres requires you to explicitly enable the array type extension before you can use array columns.

To resolve this issue and enable support for arrays in Postgres when using TypeORM, you need to follow these steps:

1. **Install the TypeORM-Array extension**: To enable array support in TypeORM for Postgres, you can use the `typeorm-arrays` package. Install the package by running the following command in your project directory:

npm install typeorm-arrays

2. **Enable the array type extension in Postgres**: Once you have installed the `typeorm-arrays` package, you need to enable the array type extension in your Postgres database. You can do this by executing the following SQL command in your database:

CREATE EXTENSION IF NOT EXISTS "uuid-ossp";

3. **Define array columns in your TypeORM entities**: After installing the `typeorm-arrays` package and enabling the array type extension in your database, you can now define array columns in your TypeORM entities. To create an array column, use the `@ArrayColumn` decorator provided by the `typeorm-arrays` package in your entity class:

import { Entity, PrimaryGeneratedColumn } from 'typeorm';
import { ArrayColumn } from 'typeorm-arrays';

@Entity()
export class MyEntity {
  @PrimaryGeneratedColumn()
  id: number;

  @ArrayColumn({ type: 'varchar', array: true, default: [] })
  myArray: string[];
}

By following these steps, you can successfully use arrays in your TypeORM entities when working with a Postgres database. This workaround allows you to take advantage of Postgres' array support while leveraging the powerful features of TypeORM in your application development.

Now that you know how to enable array support in Postgres with TypeORM, you can enhance your database schema with array columns and efficiently manage array data in your applications. Happy coding!