osdir.com


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [DISCUSS] Flink SQL DDL Design


Hi Shuyi,

It seems that you have reviewed the DDL doc [1] that Lin and I drafted.
This doc covers all the features running in Alibaba.
But some of features might be not needed in the first version of Flink SQL
DDL.

So my suggestion would be to focus on the MVP DDLs and reach agreement ASAP
based on the DDL draft [1] and the DDL design [2] Shuyi proposed.
And we can discuss on the main differences one by one.

The following is the MVP DDLs should be included in the first version in my
opinion (feedbacks are welcome):
(1) Table DDL:
    (1.1) Type definition
    (1.2) computed column definition
    (1.3) watermark definition
    (1.4) with properties
    (1.5) table constraint (primary key/unique)
    (1.6) column nullability (nice to have)
(2) View DDL
(3) Function DDL

The main differences from two DDL docs (sth maybe missed, welcome to point
out):
*(1.3) watermark*: this is the main and the most important difference, it
would be great if @Timo Walther <twalthr@xxxxxxxxxx>  @Fabian Hueske
<fhueske@xxxxxxxxx>  give some feedbacks.
 (1.1) Type definition:
      (a) Should VARCHAR carry a length, e.g. VARCHAR(128) ?
           In most cases, the varchar length is not used because they are
stored as String in Flink. But it can be used to optimize in the future if
we know the column is a fixed length VARCHAR.
           So IMO, we can support VARCHAR with length in the future, and
just VARCHAR in this version.
      (b) Should DECIMAL support custom scale and precision, e.g.
DECIMAL(12, 5)?
           If we clearly know the scale and precision of the Decimal, we
can have some optimization on serialization/deserialization. IMO, we can
support just support DECIMAL in this version,
           which means DECIMAL(38, 18) as default. And support custom scale
and precision in the future.
 (2) View DDL: Do we need WITH properties in View DDL (proposed in doc[2])?
What are the properties on the view used for?


The features could be supported and discussed in the future:
(1) period definition on table
(2) Type DDL
(3) Index DDL
(4) Library DDL
(5) Drop statement

[1] Flink DDL draft by Lin and Jark:
https://docs.google.com/document/d/1o16jC-AxnZoxMfHQptkKQkSC6ZDDBRhKg6gm8VGnY-k/edit#
[2] Flink SQL DDL design by Shuyi:
https://docs.google.com/document/d/1TTP-GCC8wSsibJaSUyFZ_5NBAHYEB1FVmPpP7RgDGBA/edit#

Cheers,
Jark

On Thu, 29 Nov 2018 at 16:13, Shaoxuan Wang <wshaoxuan@xxxxxxxxx> wrote:

> Sure Shuyu,
> What I hope is that we can reach an agreement on DDL gramma as soon as
> possible. There are a few differences between your proposal and ours. Once
> Lin and Jark propose our design, we can quickly discuss on the those
> differences, and see how far away towards a unified design.
>
> WRT the external catalog, I think it is an orthogonal topic, we can design
> it in parallel. I believe @Xuefu, @Bowen are already working on. We
> should/will definitely involve them to review the final design of DDL
> implementation. I would suggest that we should give it a higher priority on
> the DDL implementation, as it is a crucial component for the user
> experience of SQL_CLI.
>
> Regards,
> Shaoxuan
>
>
>
> On Thu, Nov 29, 2018 at 6:56 AM Shuyi Chen <suez1224@xxxxxxxxx> wrote:
>
> > Thanks a lot, Shaoxuan, Jack and Lin. We should definitely collaborate
> > here, we have also our own DDL implementation running in production for
> > almost 2 years at Uber. With the joint experience from both companies, we
> > can definitely make the Flink SQL DDL better.
> >
> > As @shaoxuan suggest, Jark can come up with a doc that talks about the
> > current DDL design in Alibaba, and we can discuss and merge them into
> one,
> > make it as a FLIP, and plan the tasks for implementation. Also, we should
> > take into account the new external catalog effort in the design. What do
> > you guys think?
> >
> > Shuyi
> >
> > On Wed, Nov 28, 2018 at 6:45 AM Jark Wu <imjark@xxxxxxxxx> wrote:
> >
> > > Hi Shaoxuan,
> > >
> > > I think summarizing it into a google doc is a good idea. We will
> prepare
> > it
> > > in the next few days.
> > >
> > > Thanks,
> > > Jark
> > >
> > > Shaoxuan Wang <wshaoxuan@xxxxxxxxx> 于2018年11月28日周三 下午9:17写道:
> > >
> > > > Hi Lin and Jark,
> > > > Thanks for sharing those details. Can you please consider summarizing
> > > your
> > > > DDL design into a google doc.
> > > > We can still continue the discussions on Shuyi's proposal. But
> having a
> > > > separate google doc will be easy for the DEV to
> > > understand/comment/discuss
> > > > on your proposed DDL implementation.
> > > >
> > > > Regards,
> > > > Shaoxuan
> > > >
> > > >
> > > > On Wed, Nov 28, 2018 at 7:39 PM Jark Wu <imjark@xxxxxxxxx> wrote:
> > > >
> > > > > Hi Shuyi,
> > > > >
> > > > > Thanks for bringing up this discussion and the awesome work! I have
> > > left
> > > > > some comments in the doc.
> > > > >
> > > > > I want to share something more about the watermark definition
> learned
> > > > from
> > > > > Alibaba.
> > > > >
> > > > >    1.
> > > > >
> > > > >    Table should be able to accept multiple watermark definition.
> > > > >
> > > > >    Because a table may have more than one rowtime field. For
> example,
> > > one
> > > > >    rowtime field is from existing field but missing in some
> records,
> > > > > another
> > > > >    is the ingestion timestamp in Kafka but not very accurate. In
> this
> > > > case,
> > > > >    user may define two rowtime fields with watermarks in the Table
> > and
> > > > > choose
> > > > >    one in different situation.
> > > > >    2.
> > > > >
> > > > >    Watermark stragety always work with rowtime field together.
> > > > >
> > > > > Based on the two points metioned above, I think we should combine
> the
> > > > > watermark strategy and rowtime field selection (i.e. which existing
> > > field
> > > > > used to generate watermark) in one clause, so that we can define
> > > multiple
> > > > > watermarks in one Table.
> > > > >
> > > > > Here I will share the watermark syntax used in Alibaba (simply
> > > modified):
> > > > >
> > > > > watermarkDefinition:
> > > > > WATERMARK [watermarkName] FOR <rowtime_field> AS wm_strategy
> > > > >
> > > > > wm_strategy:
> > > > >   BOUNDED WITH OFFSET 'string' timeUnit
> > > > > |
> > > > >   ASCENDING
> > > > >
> > > > > The “WATERMARK” keyword starts a watermark definition. The “FOR”
> > > keyword
> > > > > defines which existing field used to generate watermark, this field
> > > > should
> > > > > already exist in the schema (we can use computed-column to derive
> > from
> > > > > other fields). The “AS” keyword defines watermark strategy, such as
> > > > BOUNDED
> > > > > WITH OFFSET (covers almost all the requirements) and ASCENDING.
> > > > >
> > > > > When the expected rowtime field does not exist in the schema, we
> can
> > > use
> > > > > computed-column syntax to derive it from other existing fields
> using
> > > > > built-in functions or user defined functions. So the
> > rowtime/watermark
> > > > > definition doesn’t need to care about “field-change” strategy
> > > > > (replace/add/from-field). And the proctime field definition can
> also
> > be
> > > > > defined using computed-column. Such as pt as PROCTIME() which
> > defines a
> > > > > proctime field named “pt” in the schema.
> > > > >
> > > > > Looking forward to working with you guys!
> > > > >
> > > > > Best,
> > > > > Jark Wu
> > > > >
> > > > >
> > > > > Lin Li <lincoln.86xy@xxxxxxxxx> 于2018年11月28日周三 下午6:33写道:
> > > > >
> > > > > > @Shuyi
> > > > > > Thanks for the proposal!  We have a simple DDL implementation
> > > (extends
> > > > > > Calcite's parser) which been running for almost two years on
> > > production
> > > > > and
> > > > > > works well.
> > > > > > I think the most valued things we'd learned is keeping simplicity
> > and
> > > > > > standard compliance.
> > > > > > Here's the approximate grammar, FYI
> > > > > > CREATE TABLE
> > > > > >
> > > > > > CREATE TABLE tableName(
> > > > > >         columnDefinition [, columnDefinition]*
> > > > > >         [ computedColumnDefinition [, computedColumnDefinition]*
> ]
> > > > > >         [ tableConstraint [, tableConstraint]* ]
> > > > > >         [ tableIndex [, tableIndex]* ]
> > > > > >     [ PERIOD FOR SYSTEM_TIME ]
> > > > > >         [ WATERMARK watermarkName FOR rowTimeColumn AS
> > > > > > withOffset(rowTimeColumn, offset) ]     ) [ WITH ( tableOption [
> ,
> > > > > > tableOption]* ) ] [ ; ]
> > > > > >
> > > > > > columnDefinition ::=
> > > > > >         columnName dataType [ NOT NULL ]
> > > > > >
> > > > > > dataType  ::=
> > > > > >         {
> > > > > >           [ VARCHAR ]
> > > > > >           | [ BOOLEAN ]
> > > > > >           | [ TINYINT ]
> > > > > >           | [ SMALLINT ]
> > > > > >           | [ INT ]
> > > > > >           | [ BIGINT ]
> > > > > >           | [ FLOAT ]
> > > > > >           | [ DECIMAL ]
> > > > > >           | [ DOUBLE ]
> > > > > >           | [ DATE ]
> > > > > >           | [ TIME ]
> > > > > >           | [ TIMESTAMP ]
> > > > > >           | [ VARBINARY ]
> > > > > >         }
> > > > > >
> > > > > > computedColumnDefinition ::=
> > > > > >         columnName AS computedColumnExpression
> > > > > >
> > > > > > tableConstraint ::=
> > > > > >     { PRIMARY KEY | UNIQUE }
> > > > > >         (columnName [, columnName]* )
> > > > > >
> > > > > > tableIndex ::=
> > > > > >         [ UNIQUE ] INDEX indexName
> > > > > >          (columnName [, columnName]* )
> > > > > >
> > > > > > rowTimeColumn ::=
> > > > > >         columnName
> > > > > >
> > > > > > tableOption ::=
> > > > > >         property=value
> > > > > >         offset ::=
> > > > > >         positive integer (unit: ms)
> > > > > >
> > > > > > CREATE VIEW
> > > > > >
> > > > > > CREATE VIEW viewName
> > > > > >   [
> > > > > >         ( columnName [, columnName]* )
> > > > > >   ]
> > > > > >         AS queryStatement;
> > > > > >
> > > > > > CREATE FUNCTION
> > > > > >
> > > > > >  CREATE FUNCTION functionName
> > > > > >   AS 'className';
> > > > > >
> > > > > >  className ::=
> > > > > >         fully qualified name
> > > > > >
> > > > > >
> > > > > > Shuyi Chen <suez1224@xxxxxxxxx> 于2018年11月28日周三 上午3:28写道:
> > > > > >
> > > > > > > Thanks a lot, Timo and Xuefu. Yes, I think we can finalize the
> > > design
> > > > > doc
> > > > > > > first and start implementation w/o the unified connector API
> > ready
> > > by
> > > > > > > skipping some featue.
> > > > > > >
> > > > > > > Xuefu, I like the idea of making Flink specific properties into
> > > > generic
> > > > > > > key-value pairs, so that it will make integration with Hive DDL
> > (or
> > > > > > others,
> > > > > > > e.g. Beam DDL) easier.
> > > > > > >
> > > > > > > I'll run a final pass over the design doc and finalize the
> design
> > > in
> > > > > the
> > > > > > > next few days. And we can start creating tasks and collaborate
> on
> > > the
> > > > > > > implementation. Thanks a lot for all the comments and inputs.
> > > > > > >
> > > > > > > Cheers!
> > > > > > > Shuyi
> > > > > > >
> > > > > > > On Tue, Nov 27, 2018 at 7:02 AM Zhang, Xuefu <
> > > > xuefu.z@xxxxxxxxxxxxxxx>
> > > > > > > wrote:
> > > > > > >
> > > > > > > > Yeah! I agree with Timo that DDL can actually proceed w/o
> being
> > > > > blocked
> > > > > > > by
> > > > > > > > connector API. We can leave the unknown out while defining
> the
> > > > basic
> > > > > > > syntax.
> > > > > > > >
> > > > > > > > @Shuyi
> > > > > > > >
> > > > > > > > As commented in the doc, I think we can probably stick with
> > > simple
> > > > > > syntax
> > > > > > > > with general properties, without extending the syntax too
> much
> > > that
> > > > > it
> > > > > > > > mimics the descriptor API.
> > > > > > > >
> > > > > > > > Part of our effort on Flink-Hive integration is also to make
> > DDL
> > > > > syntax
> > > > > > > > compatible with Hive's. The one in the current proposal seems
> > > > making
> > > > > > our
> > > > > > > > effort more challenging.
> > > > > > > >
> > > > > > > > We can help and collaborate. At this moment, I think we can
> > > > finalize
> > > > > on
> > > > > > > > the proposal and then we can divide the tasks for better
> > > > > collaboration.
> > > > > > > >
> > > > > > > > Please let me know if there are  any questions or
> suggestions.
> > > > > > > >
> > > > > > > > Thanks,
> > > > > > > > Xuefu
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > ------------------------------------------------------------------
> > > > > > > > Sender:Timo Walther <twalthr@xxxxxxxxxx>
> > > > > > > > Sent at:2018 Nov 27 (Tue) 16:21
> > > > > > > > Recipient:dev <dev@xxxxxxxxxxxxxxxx>
> > > > > > > > Subject:Re: [DISCUSS] Flink SQL DDL Design
> > > > > > > >
> > > > > > > > Thanks for offering your help here, Xuefu. It would be great
> to
> > > > move
> > > > > > > > these efforts forward. I agree that the DDL is somehow
> releated
> > > to
> > > > > the
> > > > > > > > unified connector API design but we can also start with the
> > basic
> > > > > > > > functionality now and evolve the DDL during this release and
> > next
> > > > > > > releases.
> > > > > > > >
> > > > > > > > For example, we could identify the MVP DDL syntax that skips
> > > > defining
> > > > > > > > key constraints and maybe even time attributes. This DDL
> could
> > be
> > > > > used
> > > > > > > > for batch usecases, ETL, and materializing SQL queries (no
> time
> > > > > > > > operations like windows).
> > > > > > > >
> > > > > > > > The unified connector API is high on our priority list for
> the
> > > 1.8
> > > > > > > > release. I will try to update the document until mid of next
> > > week.
> > > > > > > >
> > > > > > > >
> > > > > > > > Regards,
> > > > > > > >
> > > > > > > > Timo
> > > > > > > >
> > > > > > > >
> > > > > > > > Am 27.11.18 um 08:08 schrieb Shuyi Chen:
> > > > > > > > > Thanks a lot, Xuefu. I was busy for some other stuff for
> the
> > > > last 2
> > > > > > > > weeks,
> > > > > > > > > but we are definitely interested in moving this forward. I
> > > think
> > > > > once
> > > > > > > the
> > > > > > > > > unified connector API design [1] is done, we can finalize
> the
> > > DDL
> > > > > > > design
> > > > > > > > as
> > > > > > > > > well and start creating concrete subtasks to collaborate on
> > the
> > > > > > > > > implementation with the community.
> > > > > > > > >
> > > > > > > > > Shuyi
> > > > > > > > >
> > > > > > > > > [1]
> > > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> https://docs.google.com/document/d/1Yaxp1UJUFW-peGLt8EIidwKIZEWrrA-pznWLuvaH39Y/edit?usp=sharing
> > > > > > > > >
> > > > > > > > > On Mon, Nov 26, 2018 at 7:01 PM Zhang, Xuefu <
> > > > > > xuefu.z@xxxxxxxxxxxxxxx>
> > > > > > > > > wrote:
> > > > > > > > >
> > > > > > > > >> Hi Shuyi,
> > > > > > > > >>
> > > > > > > > >> I'm wondering if you folks still have the bandwidth
> working
> > on
> > > > > this.
> > > > > > > > >>
> > > > > > > > >> We have some dedicated resource and like to move this
> > forward.
> > > > We
> > > > > > can
> > > > > > > > >> collaborate.
> > > > > > > > >>
> > > > > > > > >> Thanks,
> > > > > > > > >>
> > > > > > > > >> Xuefu
> > > > > > > > >>
> > > > > > > > >>
> > > > > > > > >>
> > > > ------------------------------------------------------------------
> > > > > > > > >> 发件人:wenlong.lwl<wenlong88.lwl@xxxxxxxxx>
> > > > > > > > >> 日 期:2018年11月05日 11:15:35
> > > > > > > > >> 收件人:<dev@xxxxxxxxxxxxxxxx>
> > > > > > > > >> 主 题:Re: [DISCUSS] Flink SQL DDL Design
> > > > > > > > >>
> > > > > > > > >> Hi, Shuyi, thanks for the proposal.
> > > > > > > > >>
> > > > > > > > >> I have two concerns about the table ddl:
> > > > > > > > >>
> > > > > > > > >> 1. how about remove the source/sink mark from the ddl,
> > because
> > > > it
> > > > > is
> > > > > > > not
> > > > > > > > >> necessary, the framework determine the table referred is a
> > > > source
> > > > > > or a
> > > > > > > > sink
> > > > > > > > >> according to the context of the query using the table. it
> > will
> > > > be
> > > > > > more
> > > > > > > > >> convenient for use defining a table which can be both a
> > source
> > > > and
> > > > > > > sink,
> > > > > > > > >> and more convenient for catalog to persistent and manage
> the
> > > > meta
> > > > > > > infos.
> > > > > > > > >>
> > > > > > > > >> 2. how about just keeping one pure string map as
> parameters
> > > for
> > > > > > table,
> > > > > > > > like
> > > > > > > > >> create tabe Kafka10SourceTable (
> > > > > > > > >> intField INTEGER,
> > > > > > > > >> stringField VARCHAR(128),
> > > > > > > > >> longField BIGINT,
> > > > > > > > >> rowTimeField TIMESTAMP
> > > > > > > > >> ) with (
> > > > > > > > >> connector.type = ’kafka’,
> > > > > > > > >> connector.property-version = ’1’,
> > > > > > > > >> connector.version = ’0.10’,
> > > > > > > > >> connector.properties.topic = ‘test-kafka-topic’,
> > > > > > > > >> connector.properties.startup-mode = ‘latest-offset’,
> > > > > > > > >> connector.properties.specific-offset = ‘offset’,
> > > > > > > > >> format.type = 'json'
> > > > > > > > >> format.prperties.version=’1’,
> > > > > > > > >> format.derive-schema = 'true'
> > > > > > > > >> );
> > > > > > > > >> Because:
> > > > > > > > >> 1. in TableFactory, what user use is a string map
> > properties,
> > > > > > defining
> > > > > > > > >> parameters by string-map can be the closest way to mapping
> > how
> > > > > user
> > > > > > > use
> > > > > > > > the
> > > > > > > > >> parameters.
> > > > > > > > >> 2. The table descriptor can be extended by user, like what
> > is
> > > > done
> > > > > > in
> > > > > > > > Kafka
> > > > > > > > >> and Json, it means that the parameter keys in connector or
> > > > format
> > > > > > can
> > > > > > > be
> > > > > > > > >> different in different implementation, we can not restrict
> > the
> > > > key
> > > > > > in
> > > > > > > a
> > > > > > > > >> specified set, so we need a map in connector scope and a
> map
> > > in
> > > > > > > > >> connector.properties scope. why not just give user a
> single
> > > map,
> > > > > let
> > > > > > > > them
> > > > > > > > >> put parameters in a format they like, which is also the
> > > simplest
> > > > > way
> > > > > > > to
> > > > > > > > >> implement DDL parser.
> > > > > > > > >> 3. whether we can define a format clause or not, depends
> on
> > > the
> > > > > > > > >> implementation of the connector, using different clause in
> > DDL
> > > > may
> > > > > > > make
> > > > > > > > a
> > > > > > > > >> misunderstanding that we can combine the connectors with
> > > > arbitrary
> > > > > > > > formats,
> > > > > > > > >> which may not work actually.
> > > > > > > > >>
> > > > > > > > >> On Sun, 4 Nov 2018 at 18:25, Dominik Wosiński <
> > > wossyn@xxxxxxxxx
> > > > >
> > > > > > > wrote:
> > > > > > > > >>
> > > > > > > > >>> +1, Thanks for the proposal.
> > > > > > > > >>>
> > > > > > > > >>> I guess this is a long-awaited change. This can vastly
> > > increase
> > > > > the
> > > > > > > > >>> functionalities of the SQL Client as it will be possible
> to
> > > use
> > > > > > > complex
> > > > > > > > >>> extensions like for example those provided by Apache
> > > Bahir[1].
> > > > > > > > >>>
> > > > > > > > >>> Best Regards,
> > > > > > > > >>> Dom.
> > > > > > > > >>>
> > > > > > > > >>> [1]
> > > > > > > > >>> https://github.com/apache/bahir-flink
> > > > > > > > >>>
> > > > > > > > >>> sob., 3 lis 2018 o 17:17 Rong Rong <walterddr@xxxxxxxxx>
> > > > > > napisał(a):
> > > > > > > > >>>
> > > > > > > > >>>> +1. Thanks for putting the proposal together Shuyi.
> > > > > > > > >>>>
> > > > > > > > >>>> DDL has been brought up in a couple of times previously
> > > [1,2].
> > > > > > > > >> Utilizing
> > > > > > > > >>>> DDL will definitely be a great extension to the current
> > > Flink
> > > > > SQL
> > > > > > to
> > > > > > > > >>>> systematically support some of the previously brought up
> > > > > features
> > > > > > > such
> > > > > > > > >> as
> > > > > > > > >>>> [3]. And it will also be beneficial to see the document
> > > > closely
> > > > > > > > aligned
> > > > > > > > >>>> with the previous discussion for unified SQL connector
> API
> > > > [4].
> > > > > > > > >>>>
> > > > > > > > >>>> I also left a few comments on the doc. Looking forward
> to
> > > the
> > > > > > > > alignment
> > > > > > > > >>>> with the other couple of efforts and contributing to
> them!
> > > > > > > > >>>>
> > > > > > > > >>>> Best,
> > > > > > > > >>>> Rong
> > > > > > > > >>>>
> > > > > > > > >>>> [1]
> > > > > > > > >>>>
> > > > > > > > >>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> http://mail-archives.apache.org/mod_mbox/flink-dev/201805.mbox/%3CCAMZk55ZTJA7MkCK1Qu4gLPu1P9neqCfHZtTcgLfrFjfO4Xv5YQ%40mail.gmail.com%3E
> > > > > > > > >>>> [2]
> > > > > > > > >>>>
> > > > > > > > >>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> http://mail-archives.apache.org/mod_mbox/flink-dev/201810.mbox/%3CDC070534-0782-4AFD-8A85-8A82B384B8F7%40gmail.com%3E
> > > > > > > > >>>> [3] https://issues.apache.org/jira/browse/FLINK-8003
> > > > > > > > >>>> [4]
> > > > > > > > >>>>
> > > > > > > > >>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> http://mail-archives.apache.org/mod_mbox/flink-dev/201810.mbox/%3C6676cb66-6f31-23e1-eff5-2e9c19f88483@xxxxxxxxxx%3E
> > > > > > > > >>>>
> > > > > > > > >>>> On Fri, Nov 2, 2018 at 10:22 AM Bowen Li <
> > > bowenli86@xxxxxxxxx
> > > > >
> > > > > > > wrote:
> > > > > > > > >>>>
> > > > > > > > >>>>> Thanks Shuyi!
> > > > > > > > >>>>>
> > > > > > > > >>>>> I left some comments there. I think the design of SQL
> DDL
> > > and
> > > > > > > > >>> Flink-Hive
> > > > > > > > >>>>> integration/External catalog enhancements will work
> > closely
> > > > > with
> > > > > > > each
> > > > > > > > >>>>> other. Hope we are well aligned on the directions of
> the
> > > two
> > > > > > > designs,
> > > > > > > > >>>> and I
> > > > > > > > >>>>> look forward to working with you guys on both!
> > > > > > > > >>>>>
> > > > > > > > >>>>> Bowen
> > > > > > > > >>>>>
> > > > > > > > >>>>>
> > > > > > > > >>>>> On Thu, Nov 1, 2018 at 10:57 PM Shuyi Chen <
> > > > suez1224@xxxxxxxxx
> > > > > >
> > > > > > > > >> wrote:
> > > > > > > > >>>>>> Hi everyone,
> > > > > > > > >>>>>>
> > > > > > > > >>>>>> SQL DDL support has been a long-time ask from the
> > > community.
> > > > > > > > >> Current
> > > > > > > > >>>>> Flink
> > > > > > > > >>>>>> SQL support only DML (e.g. SELECT and INSERT
> > statements).
> > > In
> > > > > its
> > > > > > > > >>>> current
> > > > > > > > >>>>>> form, Flink SQL users still need to define/create
> table
> > > > > sources
> > > > > > > and
> > > > > > > > >>>> sinks
> > > > > > > > >>>>>> programmatically in Java/Scala. Also, in SQL Client,
> > > without
> > > > > DDL
> > > > > > > > >>>> support,
> > > > > > > > >>>>>> the current implementation does not allow dynamical
> > > creation
> > > > > of
> > > > > > > > >>> table,
> > > > > > > > >>>>> type
> > > > > > > > >>>>>> or functions with SQL, this adds friction for its
> > > adoption.
> > > > > > > > >>>>>>
> > > > > > > > >>>>>> I drafted a design doc [1] with a few other community
> > > > members
> > > > > > that
> > > > > > > > >>>>> proposes
> > > > > > > > >>>>>> the design and implementation for adding DDL support
> in
> > > > Flink.
> > > > > > The
> > > > > > > > >>>>> initial
> > > > > > > > >>>>>> design considers DDL for table, view, type, library
> and
> > > > > > function.
> > > > > > > > >> It
> > > > > > > > >>>> will
> > > > > > > > >>>>>> be great to get feedback on the design from the
> > community,
> > > > and
> > > > > > > > >> align
> > > > > > > > >>>> with
> > > > > > > > >>>>>> latest effort in unified SQL connector API [2] and
> Flink
> > > > Hive
> > > > > > > > >>>>> integration
> > > > > > > > >>>>>> [3].
> > > > > > > > >>>>>>
> > > > > > > > >>>>>> Any feedback is highly appreciated.
> > > > > > > > >>>>>>
> > > > > > > > >>>>>> Thanks
> > > > > > > > >>>>>> Shuyi Chen
> > > > > > > > >>>>>>
> > > > > > > > >>>>>> [1]
> > > > > > > > >>>>>>
> > > > > > > > >>>>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> https://docs.google.com/document/d/1TTP-GCC8wSsibJaSUyFZ_5NBAHYEB1FVmPpP7RgDGBA/edit?usp=sharing
> > > > > > > > >>>>>> [2]
> > > > > > > > >>>>>>
> > > > > > > > >>>>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> https://docs.google.com/document/d/1Yaxp1UJUFW-peGLt8EIidwKIZEWrrA-pznWLuvaH39Y/edit?usp=sharing
> > > > > > > > >>>>>> [3]
> > > > > > > > >>>>>>
> > > > > > > > >>>>>>
> > > > > > > > >>
> > > > > > > >
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> https://docs.google.com/document/d/1SkppRD_rE3uOKSN-LuZCqn4f7dz0zW5aa6T_hBZq5_o/edit?usp=sharing
> > > > > > > > >>>>>> --
> > > > > > > > >>>>>> "So you have to trust that the dots will somehow
> connect
> > > in
> > > > > your
> > > > > > > > >>>> future."
> > > > > > > > >>
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > "So you have to trust that the dots will somehow connect in
> your
> > > > > future."
> > > > > > >
> > > > > >
> > > > >
> > > >
> > >
> >
> >
> > --
> > "So you have to trust that the dots will somehow connect in your future."
> >
>