Sergi, I still thinks my solution works or can be made to work. In the
example you provided, you can choose to return either String or Enum as the
query result. However, this is not a clean solution, I agree, but could be
a quick one.
I don't mind breaking compatibility on this issue, given that it never
worked properly anyway. Can you please file a ticket?
D.
On Wed, Jul 27, 2016 at 3:01 AM, Sergi Vladykin <sergi.vlady...@gmail.com>
wrote:
> Nope. This will not work. Because take for example the following query:
>
> select my_enum_field from my_table where my_enum_field = 'BLA'
>
> Field well be evaluated only once here, but it must be a Sting and Enum at
> the same time.
> Probably we could contribute to H2 `User defined value types` and handle
> this stuff in our own Enum value types, which will support comparison with
> String. But this requires bug H2 Modification and is a compatibility
> breaking change.
>
> Sergi
>
>
>
> 2016-07-27 9:23 GMT+03:00 Dmitriy Setrakyan <dsetrak...@apache.org>:
>
> > Hm... I would prefer to find a way to handle Enums automatically.
> >
> > In case if user expects a String, can we catch an exception and do
> > automatic conversion at that time? In this case, we could catch the
> > exception once and remember the decision. Will something like this work?
> >
> > D.
> >
> > On Tue, Jul 26, 2016 at 1:49 AM, Sergi Vladykin <
> sergi.vlady...@gmail.com>
> > wrote:
> >
> > > GridQueryProcessor contains two types: BinaryProperty and
> ClassProperty.
> > > Indexing uses them for fields access. Probably we can change them, so
> > that
> > > they will always return String instead of Enum type but this
> > >
> > > 1. looks like a compatibility breaking change;
> > > 2. users doing queries like `select my_enum_field from my_table`
> probably
> > > still expect to get a Enum result but not a String.
> > >
> > > What do you think?
> > >
> > > Sergi
> > >
> > >
> > > 2016-07-26 3:17 GMT+03:00 Valentin Kulichenko <
> > > valentin.kuliche...@gmail.com
> > > >:
> > >
> > > > Sergi,
> > > >
> > > > Ideally, I would like this query to work:
> > > >
> > > > select * from MyTable where myEnumField = 'MY_ENUM_NAME'
> > > >
> > > > The problem is that the field value is not a string, it's a binary
> > object
> > > > with the enum value ordinal inside. We can add enum value names into
> > the
> > > > metadata, so that we can always map the field value to its string
> > > > representation, but SQL engine will have to know how to use it. Is
> this
> > > > possible?
> > > >
> > > > -Val
> > > >
> > > > On Fri, Jul 22, 2016 at 10:25 PM, Sergi Vladykin <
> > > sergi.vlady...@gmail.com
> > > > > wrote:
> > > >
> > > >> I'm not sure what exactly you are going to patch in SQL engine. We
> > could
> > > >> and some SQL function like enum('MY_ENUM_NAME') but probably it will
> > not
> > > >> work if we will not pass enum type there as well, so it have look
> like
> > > >> enum('com.mycompany.MyEnum', 'MY_ENUM_NAME') which is ugly.
> > > >>
> > > >> Sergi
> > > >>
> > > >> On 23 июля 2016 г., 0:43, Valentin Kulichenko <
> > > >> valentin.kuliche...@gmail.com
> > > >> > wrote:
> > > >>
> > > >> > Folks,
> > > >> >
> > > >> > I noticed that we currently have a very weird limitation for enum
> > > fields
> > > >> > when running SQL queries. Basically, you can't use enum value
> names
> > as
> > > >> many
> > > >> > users would expect.
> > > >> >
> > > >> > Technically this happens because binary format stores only ordinal
> > and
> > > >> the
> > > >> > only way to run such query is to do something like this:
> > > >> >
> > > >> > SqlFieldsQuery qry = new SqlFieldsQuery("select * from Table where
> > > >> > enumField = ?");
> > > >> > qry.setArgs(MyEnum.ENUM_VALUE);
> > > >> > cache.query(qry);
> > > >> >
> > > >> > This means that this query can be executed only if:
> > > >> > - IgniteCache API is used. So it doesn't work in JDBC driver,
> > > Zeppelin,
> > > >> > etc.
> > > >> > - The client that executes the query has the enum class on
> > classpath.
> > > >> >
> > > >> > My first thought about fixing this is to somehow store value names
> > in
> > > >> > binary metadata and patch the SQL engine so that it understands
> how
> > to
> > > >> use
> > > >> > this information.
> > > >> >
> > > >> > Thoughts?
> > > >> >
> > > >> > -Val
> > > >> >
> > > >>
> > > >
> > > >
> > >
> >
>
