How do I handle nested transactions in Sequelize?

How do I handle nested transactions in Sequelize?

In Sequelize, you can handle nested transactions by creating a transaction within another transaction. You can use the transaction method to achieve this.

Can you provide a code example for that?

Sure! Here's a simple example:

const { Sequelize, Transaction } = require('sequelize');
const sequelize = new Sequelize('database', 'username', 'password', { dialect: 'mysql' });

async function runTransactions() {
    const t1 = await sequelize.transaction();
    try {
        // First transaction
        await Model1.create({ /* data */ }, { transaction: t1 });
        const t2 = await sequelize.transaction();
        try {
            // Nested transaction
            await Model2.create({ /* data */ }, { transaction: t2 });
            await t2.commit();
        } catch (error) {
            await t2.rollback();
            throw error;
        }
        await t1.commit();
    } catch (error) {
        await t1.rollback();
        console.error('Transaction failed:', error);
    }
}

What happens if the nested transaction fails?

If the nested transaction fails, it will trigger a rollback for that transaction only. However, the outer transaction can still succeed if it doesn't depend on the nested transaction's success.