Answer by Ali Khalid for How to insert data to multiple tables in one db request with sequelize?

There is no way to create a user and add the roles at the same time unless you want to create a custom stored procedure in MySQL.

Lets try to simplify your problem. You do not know the USER ID before you create the user. Therefore it is impossible to create the role before you create the user. One way to solve this issue, is to generate the user ID in your code.

You can add an extra column in your "Users" table called GeneratedId and convert the ID column to AUTO_INCREMENT, then use a package such as https://www.npmjs.com/package/uuid to generate a unique ID before you insert the user.

Use the same generated Id to associate the role to the user (The "UserId" column in the "UserRole" table will contain the Id you generated in code).

Now you can add the user and all the associated data without waiting for the answer from the server.