Correct, it worked, because Ignite has never had real database use case in
mind. Unfortunately, if our global plans go as expected, it will not work
for Ignite 2.x+.

On Fri, Jan 13, 2017 at 11:53 AM, Sergi Vladykin <sergi.vlady...@gmail.com>
wrote:

> Lets move on with SQL schema == Ignite cache. It worked always like this, I
> see no reasons to change this.
>
> Sergi
>
> 2017-01-13 11:20 GMT+03:00 Vladimir Ozerov <voze...@gridgain.com>:
>
> > "Tablespace" (Oracle, PostgreSQL) is what maps better than "schema" to
> our
> > cache. But not ideally still.
> >
> > On Fri, Jan 13, 2017 at 11:10 AM, Vladimir Ozerov <voze...@gridgain.com>
> > wrote:
> >
> > > Alex,
> > >
> > > Currently Ignite is not used as database. It is used as search engine -
> > > several types, several tables, several joins. This is why having
> "SCHEMA
> > ==
> > > cache" was never a problem. Users have never build complex SQL
> > applications
> > > on top of Ignite. But we are going towards database. And my question
> > stands
> > > still - suppose it is Y2019, how is user going to migrate his database
> > > containing 20-30-50-100 tables in a single schema in Oracle to Ignite?
> > >
> > > Single cache for all tables? Doens't work - not flexible. Users will
> > > definitely require different cache modes, different co-location rules,
> > > different number of backups, etc..
> > > Schema per table? Doesn't work either - unmanageable and not convenient
> > > for users even for relatively small databases.
> > >
> > > From user perspective schema is logical grouping of database objects,
> > > nothing more.
> > >
> > > For Ignite schema could be a logical group of resources (nodes, memory
> > > pools, caches, etc.). And multiple tables over multiple caches should
> > > reside in it. To the contrast, table definition governs how data is
> > stored.
> > > This is similar to, for example, MySQL approach, where you define how
> you
> > > store data on per-table level, and on schema level you define only
> minor
> > > things like collation.
> > >
> > > Vladimir.
> > >
> > >
> > > On Fri, Jan 13, 2017 at 10:33 AM, Alexander Paschenko <
> > > alexander.a.pasche...@gmail.com> wrote:
> > >
> > >> Vova,
> > >>
> > >> 2017-01-13 4:56 GMT+08:00 Vladimir Ozerov <voze...@gridgain.com>:
> > >> > I am not quite sure I understand the idea of "SCHEMA == cache".
> > Consider
> > >> > some small database with, say, ~30 tables. And user wants to migrate
> > to
> > >> > Ignite. How is he supposed to do so? 30 schemas leading to rewrite
> of
> > >> all
> > >> > his SQL scripts? Or 30 key-value pairs in a single cache leading to
> > >> lack of
> > >> > flexibility and performance problems?
> > >>
> > >> But currently schema *is* semantically equal to cache while table is
> > >> equal to type descriptor (i.e. type of stored entities), nothing new
> > >> here.
> > >>
> > >> Say, in single cache we may have entities of types Person and
> > >> Organization, those map to two tables with same names, and can be
> > >> accessed within the same cache (i.e. schema).
> > >>
> > >> If we want to limit the user with having single type descriptor per
> > >> cache (i.e. cache has only one type of stored entities - BTW, where we
> > >> are with this 2.0-wise?), then this notion could change. But currently
> > >> what has been suggested already fits quite good with what we do have
> > >> at the moment regarding semantic of SQL objects.
> > >>
> > >> - Alex
> > >>
> > >> > Another example is how to deal with referene tables? Lots database
> has
> > >> > small reference tables which is best to fit REPLICATED cache, while
> > >> others
> > >> > are usually bound to PARTITIONED mode. "SCHEMA == cache" will force
> > >> users
> > >> > to split them into separate schemes leading to poor user experience.
> > >> >
> > >> > I understand that we may have some implementation details around it
> at
> > >> the
> > >> > moment. But from user perspective "SCHEMA == cache" doesn't make
> > sense.
> > >> As
> > >> > we are going towards AI 2.0 we'd better to rethink this approach.
> > >> >
> > >> > On Thu, Jan 12, 2017 at 11:46 PM, Denis Magda <dma...@apache.org>
> > >> wrote:
> > >> >
> > >> >>
> > >> >> > On Jan 12, 2017, at 12:35 PM, Dmitriy Setrakyan <
> > >> dsetrak...@apache.org>
> > >> >> wrote:
> > >> >> >
> > >> >> > On Thu, Jan 12, 2017 at 9:47 AM, Sergi Vladykin <
> > >> >> sergi.vlady...@gmail.com>
> > >> >> > wrote:
> > >> >> >
> > >> >> >> The xml config was only for example. We can put in this
> > >> configuration
> > >> >> >> string cache config parameters directly like this:
> > >> >> >>
> > >> >> >> CREATE SCHEMA "MyCacheName" WITH
> > >> >> >> "cacheMode=REPLICATED;atomicityMode=ATOMIC"
> > >> >> >>
> > >> >> >
> > >> >> > This approach makes sense, if it can be easily supported with H2.
> > >> >>
> > >> >> What’s for affinity keys? Can we make an exception for them by
> > >> defining in
> > >> >> this part of the statement
> > >> >>
> > >> >> CREATE TABLE employee (
> > >> >>    id BIGINT PRIMARY KEY,
> > >> >>    dept_id BIGINT AFFINITY KEY,
> > >> >>    name VARCHAR(128),
> > >> >> );
> > >> >>
> > >> >> or that l
> > >> >>
> > >> >> CREATE TABLE employee (
> > >> >>    id BIGINT PRIMARY KEY,
> > >> >>    dept_id BIGINT,
> > >> >>    name VARCHAR(128),
> > >> >>    CONSTRAINT affKey AFFINITY KEY(dept_id)
> > >> >> );
> > >> >>
> > >> >> ?
> > >> >>
> > >> >> —
> > >> >> Denis
> > >> >>
> > >> >>
> > >>
> > >
> > >
> >
>

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