Vova,

We need to start from performance evaluation before we integrate ANTLR into
our product. Otherwise, it will be hard to abandon it in future.

D.

On Sat, Sep 9, 2017 at 7:57 AM, Vladimir Ozerov <[email protected]>
wrote:

> Dima,
>
> Manual parsing is too hard to implement. More precisely - too time
> consuming. ANTLR will let us add more and more grammar with minimal
> efforts.
>
> Immediate benefits for the project:
> 1) Nice CREATE TABLE syntax
> 2) Ability to add any administrative commands we want. E.g. "CLUSTER
> ACTIVATE", "CREATE CACHE".
>
> Long-term benefits:
> 1) Nice syntax all over our SQL (e.g. we will be able to tune single SELECT
> with hints, instead of current ugly flags on SqlFieldsQuery)
> 2) Nice and consistent error messages
> 3) Full control on what we support and what we don't
> 4) Removing dependency on H2
>
> Performance will be evaluated separately [1].
>
> [1] https://issues.apache.org/jira/plugins/servlet/mobile#
> issue/IGNITE-6320
>
>
>
> пт, 8 сент. 2017 г. в 21:01, Dmitriy Setrakyan <[email protected]>:
>
> > Vova, license-wise it is OK, but I do not like adding the dependency.
> Right
> > now we have H2 doing parsing for us. Why would ANTLR be better? What
> > happens when we potentially notice a performance issue or any other issue
> > in ANTLR under load?
> >
> > Can we try doing parsing ourselves instead of adding a dependency?
> >
> > D.
> >
> > On Fri, Sep 8, 2017 at 2:23 AM, Vladimir Ozerov <[email protected]>
> > wrote:
> >
> > > Igniters,
> > >
> > > We are evaluating ANTLR [1] as a parser generator for our SQL engine
> [2].
> > > At first glance it looks very good, we already able to parse certain
> SQL
> > > commands with it. If implemented, it would greatly improve usability of
> > our
> > > SQL engine. However, it goes under BSD license and require one small
> > > runtime dependency "antlr-runtime" [3].
> > >
> > > I need assistance form someone with greater experience with different
> > > licences - is it fine to add this dependency to Ignite? Would it
> violate
> > > ASF licensing rules?
> > >
> > > AFAIK other ASF projects use it, e.g. Hive [4].
> > >
> > > Vladimir.
> > >
> > > [1] http://www.antlr.org/
> > > [2] https://issues.apache.org/jira/browse/IGNITE-6276
> > > [3] https://mvnrepository.com/artifact/org.antlr/antlr-runtime
> > > [4] https://github.com/apache/hive/blob/master/ql/pom.xml#L165
> > >
> >
>

Reply via email to