On Apr 9, 2009, at 5:38 PM, Boris Zbarsky wrote:
Maciej Stachowiak wrote:
I agree that "no such thing as standard SQL" (or rather the fact
that implementations all have extensions and divergences from the
spec) is a problem. But I am not sure inventing a brand new query
language and database model as proposed by Vlad is a good solution
to this problem.
That's fine; I'm not sure of that either. I have no particular
opinion on that question, in fact.
1) Applications are starting to be deployed which use the SQL-based
storage API, such as the mobile version of GMail. So it may be too
late for us to remove SQL storage from WebKit entirely.
This is a price of early adoption, sure.
If we want this content to interoperate with non-WebKit-based user
agents, then we will ultimately need a clear spec for the SQL
dialect to use, even if we also added an OODB or a relational
database using some other query language.
That's true, but it's not a given that we want this content to
interoperate as-is. Early adopters of known in-flux technologies
typically realize that they might have to make changes; if a
different data storage API is decided on, or if the subset of SQL
that's decided on doesn't match what these apps are using, then
they'll need to change.
So while I agree that it might be difficult for Webkit to remove the
SQL support it shipped as soon as some other approach is decided on
(if that even happens), it doesn't follow that other UAs would need
to ship SQL support at that point.
There are strong arguments for not breaking existing content, of
course, but there are also strong arguments for not having
experimental implementations of early drafts completely dictate the
standardization process.
I don't think this one point should be decisive by itself. But I don't
think it should be given zero weight either. I do think the existence
of an implementation of the current spec and Web content using it
somewhat raises the burden of proof on anyone proposing a redesign.
Note that one of the clients in question is the offline-enabled mobile
version of GMail. I think this demonstrates that the SQL-based
Database Storage can serve the needs of an advanced and polished Web
application. In addition, we have a rough demonstration that it is
practically implementable in a modern Web engine.
One clear problem identified despite these examples is that we do not
have a precise enough spec for the query language to make truly
independent interoperable implementations possible. It seems to me
that significantly redesigning database storage is not necessary to
address this. "X is underspecified so let's do Y or Z instead" is not
a very strong argument in my opinion. Another issue raised is that a
different database model (OODB for instance) may work better for
content authors. I would say we do not have very compelling evidence
yet that such a design would be better, or that it could meet the
various requirements, and we do not even have a concrete strawman
proposal that we could start evaluating.
Regards,
Maciej
