Forum: Ruby on Rails `build_association` produces DB-queries

Let `User.has_one :profile`. I've always thought that 
`@user.build_profile`
is a cheap thing to do - it's just creating a new object without 
persisting
it. But, in fact, it does 2 queries to the DB: `BEGIN` and `COMMIT`.

In my app I have an admin users#index page where users' details can be
edited, and to simplify the code I build a profile whenever it's `nil`, 
so
I get 2 queries for each user, which increases the page load time by a
factor. So I'd like to know if this is a bug in Rails worth fixing or 
that
transaction is really necessary when building an association?

Thanks,
Roman

On Saturday, July 28, 2012 6:08:48 PM UTC+1, Roman wrote:
>
> Let `User.has_one :profile`. I've always thought that
> `@user.build_profile` is a cheap thing to do - it's just creating a new
> object without persisting it. But, in fact, it does 2 queries to the DB:
> `BEGIN` and `COMMIT`.
>
>
I've never seen this before. Is there anything interesting about your
profile class ?

Fred