It is possible to make an insert and build associations of this insert in the same transaction?

Yes, possible. Within the transaction you can get the id of the insert.

If you use Phoenix, then probably you use Ecto as well. If not, you should, Ecto is amazing.
Check Ecto Multi.

cast_assoc and put_assoc also insert the data inside the same transaction

Thank you How ?

Yes I use Ecto Multi

OK thank you

So, this code would be correct ?

build_assoc belongs to Ecto or Ecto.Changeset ?

Multi.new()
|> Multi.insert(:insert, %Post{})
|> build_assoc(:comments)
|> build_assoc(:pictures)
|> Repo.transaction

Hi @sabo66 please do not make 4 individual posts to reply, just make one post and quote people you want to reply to inside.

I think you’re overthinking this.

1. If you use the assoc helpers a regular Repo.insert(post) call will open a transaction and insert any children in the changeset in the same transaction, so that’ll just work
2. If you want to do this manually I would consider first trying to do so without any transaction, then figure out how to do it inside a transaction.

Ok !

Ok thank you, I understand better now @benwilson512