Steps to Migrate MySQL Database to PostgreSQL

Migrating a database from MySQL to PostgreSQL requires a structured approach to ensure data integrity and minimize disruptions. In this comprehensive guide, we’ll walk you through each step of the migration process, leveraging the power of pgloader for seamless data transfer.

Step 1: Create a Sample Database in MySQL

Begin by setting up a sample MySQL database with test data. This serves as the source database for our migration process. Using your MySQL client, execute the following SQL commands:

CREATE DATABASE sample_mysql_db;
USE sample_mysql_db;

CREATE TABLE users (
    id INT PRIMARY KEY,
    name VARCHAR(255),
    email VARCHAR(255)
);

INSERT INTO users VALUES
(1, 'John Doe', 'john@example.com'),
(2, 'Jane Doe', 'jane@example.com');

This establishes a MySQL database named sample_mysql_db with a users table populated with sample data.

Step 2: Install pgloader On Your System

Ensure that pgloader is installed on your system to facilitate the migration process. Depending on your operating system, installation instructions may vary. For instance, on Ubuntu, you can install pgloader using:

sudo apt install pgloader

Step 3: Build a PostgreSQL Database and Role

Prepare a target PostgreSQL database and role to receive the migrated data. Execute the following commands within your PostgreSQL environment:

CREATE DATABASE sample_postgresql_db;
CREATE ROLE mysql_user WITH LOGIN PASSWORD 'your_password';

Substitute ‘your_password’ with a secure password of your choice.

Step 4: Create a Dedicated User in MySQL and Manage Certificates

For security purposes, it’s recommended to create a dedicated user in MySQL specifically for the migration process. Additionally, if SSL/TLS certificates are required for secure communication between MySQL and pgloader, ensure they are properly configured.

Step 5: Migration of Data

With both MySQL and PostgreSQL databases set up, it’s time to migrate the data using pgloader. Execute the following command in your terminal

pgloader mysql://mysql_user:password@localhost/sample_mysql_db \
          postgresql://postgres:password@localhost/sample_postgresql_db

Replace mysql_user, password, sample_mysql_db, postgres, and password with your MySQL username, password, database name, PostgreSQL username, and password, respectively.

pgloader will automatically migrate the data from the MySQL database to the PostgreSQL database.

Database migration is a common task in software development when switching between different database management systems (DBMS).

In this article, we’ll explore how to migrate a MySQL database to PostgreSQL using a powerful tool called pgloader. We’ll cover the concepts involved, and the steps required, and provide detailed examples with outputs to guide you through the process.