DBMS 事务：它们存储在哪里？

Question

I'm using sequelize, and using transactions, but I have to make a lot of inserts every night, my fear is if these inserts/changes are stored in memory until transaction is commited and can crash the server and lost it all. Or if these changes are stored and handled by the DBMS (in this case i'm using aurora/postgresql) and i don't have to worry about nothing

Help!

I'm usings express 4, sequelize 5 and this will run maybe on a cronJob This is an abstract example of my structure

const db = require('../database/models')

class Controller {
    async test (req, res) {
        let transaction = await db.sequelize.transaction()
        try {
            await this.storeData(req.body, transaction)
            await transaction.commit()
            res.status(200)
        } catch (error) {
            if (transaction) await transaction.rollback()
            res.status(400)
        }
    }

    async storeDate (params, transaction = null) {
        // Calculation of the data to insert
        var records = []
        await Promise.all(records.map(async item => {
                await db.MyModel.create(item, { transaction })
            }
        ))
    }

Answer 1

A transaction feature in Sequelize is just a wrapper over a DB transaction and, of course, a transactional DBMS has a transaction log and stores all ongoing transaction operations there.
One edge case would be if you really like to take too many objects and insert them all in one operation so I'd recommend to divide a huge amount of rows into smaller batches.