[hibernate-dev] More Dialect and quoting fun

[Steve Ebersole]

I actually started with the third approach.  But you bring up a good point
about allowing the Dialect to access the DatabaseMetaData (and hence
Connection) if it wanted to.  So I would change that a bit.  See the
updated gist

On Wed, May 27, 2015 at 7:33 AM, Max Rydahl Andersen <manderse at redhat.com>
wrote:

>
> > The old
> > way was calling one or more of the 50,000 (give or take ;) true/false
> > methods on Dialect at runtime.  The new evolving approach is to build
> > delegates/helpers at boot time that encapsulate all that.  Most of that
> > work so far is encapsulated by JdbcEnvironment.  One piece of this
> > JdbcEnvironment is this IdentifierHelper
> > (JdbcEnvironment#getIdentifierHelper).
> >
> > Maybe it makes the most sense to psuedo-code some approaches:
> > https://gist.github.com/sebersole/46b5b7968e748648f562
>
> Of these I think the outline in "first approach" is the best
> since it does give the Dialect a chance to actually "talk" to the
> server to figure out a possible better lookup than the jdbcDriver does.
>
> But as you said the dialect must handle getting null passed in - just don't
> see a better way to handle that.
>
> Could even keep the implicit contract of if you return null it will
> do as described in "second approach" and have a decent fallback.
>
> /max
>
>
> >
> >
> >
> >> One concern about DatabaseMetaData that hit the tools a few times is
> that
> >> getting this can be extremely expensive for some drivers (I don't recall
> >> which
> >> exactly, but Oracle comes to mind ;)
> >>
> >
> > We get this once per bootstrap.
>
>
> /max
> http://about.me/maxandersen
>