Chinedu OrieSometimes you realize that you need to add some new fields to an existing sequelize migrations. This is especially important for production apps where refreshing the migration is not an option. Below is a quick guide on how to implement it.
Let's assume you want to add some new fields to Users table; below are the steps.
Step 1 - Create a new migration
npx sequelize-cli migration:create --name modify_users_add_new_fields
Step 2 - Edit the migrations to suit the need
module.exports = {
up(queryInterface, Sequelize) {
return Promise.all([
queryInterface.addColumn(
'Users', // table name
'twitter', // new field name
{
type: Sequelize.STRING,
allowNull: true,
},
),
queryInterface.addColumn(
'Users',
'linkedin',
{
type: Sequelize.STRING,
allowNull: true,
},
),
queryInterface.addColumn(
'Users',
'bio',
{
type: Sequelize.TEXT,
allowNull: true,
},
),
]);
},
down(queryInterface, Sequelize) {
// logic for reverting the changes
return Promise.all([
queryInterface.removeColumn('Users', 'linkedin'),
queryInterface.removeColumn('Users', 'twitter'),
queryInterface.removeColumn('Users', 'bio'),
]);
},
};
Step 3 - Update the model with the new fields
Step 4 - Run migration
npx sequelize-cli db:migrate
That is it, you have successfully added new fields to an existing migration.
