How can i handle nested queries with promises instead of callback?

Question

how can i do the following with bluebird promises. modules i am using are bluebird, promise-mysql

1. insert in table A and return a_id
2. insert records in table B using a_id as foreign key
3. insert records in table C using a_id as foreign key
4. now response is send to user that all records are added.

I am using native queries.

Answer 1

The general idea is:

insetA()
  .then(function(a_id){
    return Promise.all([inserB(a_id), inserC(a_id)])
  })
  .then(function(){
     res.send("all good")
  })
  .catch(function(error){
     res.send("some error")
  })


function insetA(){
  return new Promise(function (resolve, reject) {
    // inserting A 
    // resolve(a_id)
  })
}