Sorry for the late reply. I am in favor of introducing such a built-in resource localization mechanism based on Flink FileSystem. Then FLINK-28915[1] could be the second step which will download the jars and dependencies to the JobManager/TaskManager local directory before working.
The first step could be done in another ticket in Flink. Or some external Flink jobs management system could also take care of this. [1]. https://issues.apache.org/jira/browse/FLINK-28915 Best, Yang Paul Lam <paullin3...@gmail.com> 于2023年6月9日周五 17:39写道： > Hi Mason, > > I get your point. I'm increasingly feeling the need to introduce a > built-in > file distribution mechanism for flink-kubernetes module, just like Spark > does with `spark.kubernetes.file.upload.path` [1]. > > I’m assuming the workflow is as follows: > > - KubernetesClusterDescripter uploads all local resources to a remote > storage via Flink filesystem (skips if the resources are already remote). > - KubernetesApplicationClusterEntrypoint downloads the resources > and put them in the classpath during startup. > > I wouldn't mind splitting it into another FLIP to ensure that everything is > done correctly. > > cc'ed @Yang to gather more opinions. > > [1] > https://spark.apache.org/docs/latest/running-on-kubernetes.html#dependency-management > > Best, > Paul Lam > > 2023年6月8日 12:15，Mason Chen <mas.chen6...@gmail.com> 写道： > > Hi Paul, > > Thanks for your response! > > I agree that utilizing SQL Drivers in Java applications is equally > important > > as employing them in SQL Gateway. WRT init containers, I think most > users use them just as a workaround. For example, wget a jar from the > maven repo. > > We could implement the functionality in SQL Driver in a more graceful > way and the flink-supported filesystem approach seems to be a > good choice. > > > My main point is: can we solve the problem with a design agnostic of SQL > and Stream API? I mentioned a use case where this ability is useful for > Java or Stream API applications. Maybe this is even a non-goal to your FLIP > since you are focusing on the driver entrypoint. > > Jark mentioned some optimizations: > > This allows SQLGateway to leverage some metadata caching and UDF JAR > caching for better compiling performance. > > It would be great to see this even outside the SQLGateway (i.e. UDF JAR > caching). > > Best, > Mason > > On Wed, Jun 7, 2023 at 2:26 AM Shengkai Fang <fskm...@gmail.com> wrote: > > Hi. Paul. Thanks for your update and the update makes me understand the > design much better. > > But I still have some questions about the FLIP. > > For SQL Gateway, only DMLs need to be delegated to the SQL server > Driver. I would think about the details and update the FLIP. Do you have > > some > > ideas already? > > > If the applicaiton mode can not support library mode, I think we should > only execute INSERT INTO and UPDATE/ DELETE statement in the application > mode. AFAIK, we can not support ANALYZE TABLE and CALL PROCEDURE > statements. The ANALYZE TABLE syntax need to register the statistic to the > catalog after job finishes and the CALL PROCEDURE statement doesn't > generate the ExecNodeGraph. > > * Introduce storage via option `sql-gateway.application.storage-dir` > > If we can not support to submit the jars through web submission, +1 to > introduce the options to upload the files. While I think the uploader > should be responsible to remove the uploaded jars. Can we remove the jars > if the job is running or gateway exits? > > * JobID is not avaliable > > Can we use the returned rest client by ApplicationDeployer to query the job > id? I am concerned that users don't know which job is related to the > submitted SQL. > > * Do we need to introduce a new module named flink-table-sql-runner? > > It seems we need to introduce a new module. Will the new module is > available in the distribution package? I agree with Jark that we don't need > to introduce this for table-API users and these users have their main > class. If we want to make users write the k8s operator more easily, I think > we should modify the k8s operator repo. If we don't need to support SQL > files, can we make this jar only visible in the sql-gateway like we do in > the planner loader?[1] > > [1] > > > https://github.com/apache/flink/blob/master/flink-table/flink-table-planner-loader/src/main/java/org/apache/flink/table/planner/loader/PlannerModule.java#L95 > > Best, > Shengkai > > > > > > > > > Weihua Hu <huweihua....@gmail.com> 于2023年6月7日周三 10:52写道： > > Hi, > > Thanks for updating the FLIP. > > I have two cents on the distribution of SQLs and resources. > 1. Should we support a common file distribution mechanism for k8s > application mode? > I have seen some issues and requirements on the mailing list. > In our production environment, we implement the download command in the > CliFrontend. > And automatically add an init container to the POD for file > > downloading. > > The advantage of this > is that we can use all Flink-supported file systems to store files. > > This need more discussion. I would appreciate hearing more opinions. > > 2. In this FLIP, we distribute files in two different ways in YARN and > Kubernetes. Can we combine it in one way? > If we don't want to implement a common file distribution for k8s > application mode. Could we use the SQLDriver > to download the files both in YARN and K8S? IMO, this can reduce the > > cost > > of code maintenance. > > Best, > Weihua > > > On Wed, Jun 7, 2023 at 10:18 AM Paul Lam <paullin3...@gmail.com> wrote: > > Hi Mason, > > Thanks for your input! > > +1 for init containers or a more generalized way of obtaining > > arbitrary > > files. File fetching isn't specific to just SQL--it also matters for > > Java > > applications if the user doesn't want to rebuild a Flink image and > > just > > wants to modify the user application fat jar. > > > I agree that utilizing SQL Drivers in Java applications is equally > important > as employing them in SQL Gateway. WRT init containers, I think most > users use them just as a workaround. For example, wget a jar from the > maven repo. > > We could implement the functionality in SQL Driver in a more graceful > way and the flink-supported filesystem approach seems to be a > good choice. > > Also, what do you think about prefixing the config options with > `sql-driver` instead of just `sql` to be more specific? > > > LGTM, since SQL Driver is a public interface and the options are > specific to it. > > Best, > Paul Lam > > 2023年6月6日 06:30，Mason Chen <mas.chen6...@gmail.com> 写道： > > Hi Paul, > > +1 for this feature and supporting SQL file + JSON plans. We get a > > lot > > of > > requests to just be able to submit a SQL file, but the JSON plan > optimizations make sense. > > +1 for init containers or a more generalized way of obtaining > > arbitrary > > files. File fetching isn't specific to just SQL--it also matters for > > Java > > applications if the user doesn't want to rebuild a Flink image and > > just > > wants to modify the user application fat jar. > > Please note that we could reuse the checkpoint storage like S3/HDFS, > > which > > should > > > be required to run Flink in production, so I guess that would be > > acceptable > > for most > > > users. WDYT? > > > If you do go this route, it would be nice to support writing these > > files > > to > > S3/HDFS via Flink. This makes access control and policy management > > simpler. > > > Also, what do you think about prefixing the config options with > `sql-driver` instead of just `sql` to be more specific? > > Best, > Mason > > On Mon, Jun 5, 2023 at 2:28 AM Paul Lam <paullin3...@gmail.com > > <mailto: > > paullin3...@gmail.com>> wrote: > > > Hi Jark, > > Thanks for your input! Please see my comments inline. > > Isn't Table API the same way as DataSream jobs to submit Flink SQL? > DataStream API also doesn't provide a default main class for users, > why do we need to provide such one for SQL? > > > Sorry for the confusion I caused. By DataStream jobs, I mean jobs > > submitted > > via Flink CLI which actually could be DataStream/Table jobs. > > I think a default main class would be user-friendly which eliminates > > the > > need > for users to write a main class as SQLRunner in Flink K8s operator > > [1]. > > > I thought the proposed SqlDriver was a dedicated main class > > accepting > > SQL files, is > > that correct? > > > Both JSON plans and SQL files are accepted. SQL Gateway should use > > JSON > > plans, > while CLI users may use either JSON plans or SQL files. > > Please see the updated FLIP[2] for more details. > > Personally, I prefer the way of init containers which doesn't > > depend > > on > > additional components. > This can reduce the moving parts of a production environment. > Depending on a distributed file system makes the testing, demo, and > > local > > setup harder than init containers. > > > Please note that we could reuse the checkpoint storage like S3/HDFS, > > which > > should > be required to run Flink in production, so I guess that would be > acceptable for most > users. WDYT? > > WRT testing, demo, and local setups, I think we could support the > > local > > filesystem > scheme i.e. file://** as the state backends do. It works as long as > > SQL > > Gateway > and JobManager(or SQL Driver) can access the resource directory > > (specified > > via > `sql-gateway.application.storage-dir`). > > Thanks! > > [1] > > > > > https://github.com/apache/flink-kubernetes-operator/blob/main/examples/flink-sql-runner-example/src/main/java/org/apache/flink/examples/SqlRunner.java > > [2] > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-316:+Introduce+SQL+Driver > > [3] > > > > > https://github.com/apache/flink/blob/3245e0443b2a4663552a5b707c5c8c46876c1f6d/flink-runtime/src/test/java/org/apache/flink/runtime/state/filesystem/AbstractFileCheckpointStorageAccessTestBase.java#L161 > > > Best, > Paul Lam > > 2023年6月3日 12:21，Jark Wu <imj...@gmail.com> 写道： > > Hi Paul, > > Thanks for your reply. I left my comments inline. > > As the FLIP said, it’s good to have a default main class for Flink > > SQLs, > > which allows users to submit Flink SQLs in the same way as > > DataStream > > jobs, or else users need to write their own main class. > > > Isn't Table API the same way as DataSream jobs to submit Flink SQL? > DataStream API also doesn't provide a default main class for users, > why do we need to provide such one for SQL? > > With the help of ExecNodeGraph, do we still need the serialized > SessionState? If not, we could make SQL Driver accepts two > > serialized > > formats: > > > No, ExecNodeGraph doesn't need to serialize SessionState. I thought > > the > > proposed SqlDriver was a dedicated main class accepting SQL files, > > is > > that correct? > If true, we have to ship the SessionState for this case which is a > > large > > work. > I think we just need a JsonPlanDriver which is a main class that > > accepts > > JsonPlan as the parameter. > > > The common solutions I know is to use distributed file systems or > > use > > init containers to localize the resources. > > > Personally, I prefer the way of init containers which doesn't > > depend > > on > > additional components. > This can reduce the moving parts of a production environment. > Depending on a distributed file system makes the testing, demo, and > > local > > setup harder than init containers. > > Best, > Jark > > > > > On Fri, 2 Jun 2023 at 18:10, Paul Lam <paullin3...@gmail.com > > <mailto: > > paullin3...@gmail.com> <mailto: > > paullin3...@gmail.com <mailto:paullin3...@gmail.com>>> wrote: > > > The FLIP is in the early phase and some details are not included, > > but > > fortunately, we got lots of valuable ideas from the discussion. > > Thanks to everyone who joined the dissuasion! > @Weihua @Shanmon @Shengkai @Biao @Jark > > This weekend I’m gonna revisit and update the FLIP, adding more > details. Hopefully, we can further align our opinions. > > Best, > Paul Lam > > 2023年6月2日 18:02，Paul Lam <paullin3...@gmail.com <mailto: > > paullin3...@gmail.com>> 写道： > > > Hi Jark, > > Thanks a lot for your input! > > If we decide to submit ExecNodeGraph instead of SQL file, is it > > still > > necessary to support SQL Driver? > > > I think so. Apart from usage in SQL Gateway, SQL Driver could > > simplify > > Flink SQL execution with Flink CLI. > > As the FLIP said, it’s good to have a default main class for > > Flink > > SQLs, > > which allows users to submit Flink SQLs in the same way as > > DataStream > > jobs, or else users need to write their own main class. > > SQL Driver needs to serialize SessionState which is very > > challenging > > but not detailed covered in the FLIP. > > > With the help of ExecNodeGraph, do we still need the serialized > SessionState? If not, we could make SQL Driver accepts two > > serialized > > formats: > > - SQL files for user-facing public usage > - ExecNodeGraph for internal usage > > It’s kind of similar to the relationship between job jars and > > jobgraphs. > > > Regarding "K8S doesn't support shipping multiple jars", is that > > true? > > Is it > > possible to support it? > > > Yes, K8s doesn’t distribute any files. It’s the users’ > > responsibility > > to > > make > > sure the resources are accessible in the containers. The common > > solutions > > I know is to use distributed file systems or use init containers > > to > > localize the > > resources. > > Now I lean toward introducing a fs to do the distribution job. > > WDYT? > > > Best, > Paul Lam > > 2023年6月1日 20:33，Jark Wu <imj...@gmail.com <mailto: > > imj...@gmail.com> > > <mailto:imj...@gmail.com <mailto:imj...@gmail.com>> > > <mailto:imj...@gmail.com <mailto:imj...@gmail.com> <mailto: > > imj...@gmail.com <mailto:imj...@gmail.com>>>> > > 写道： > > > Hi Paul, > > Thanks for starting this discussion. I like the proposal! This > > is > > a > > frequently requested feature! > > I agree with Shengkai that ExecNodeGraph as the submission > > object > > is a > > better idea than SQL file. To be more specific, it should be > > JsonPlanGraph > > or CompiledPlan which is the serializable representation. > > CompiledPlan > > is a > > clear separation between compiling/optimization/validation and > > execution. > > This can keep the validation and metadata accessing still on the > > SQLGateway > > side. This allows SQLGateway to leverage some metadata caching > > and > > UDF > > JAR > > caching for better compiling performance. > > If we decide to submit ExecNodeGraph instead of SQL file, is it > > still > > necessary to support SQL Driver? Regarding non-interactive SQL > > jobs, > > users > > can use the Table API program for application mode. SQL Driver > > needs > > to > > serialize SessionState which is very challenging but not > > detailed > > covered > > in the FLIP. > > Regarding "K8S doesn't support shipping multiple jars", is that > > true? > > Is it > > possible to support it? > > Best, > Jark > > > > On Thu, 1 Jun 2023 at 16:58, Paul Lam <paullin3...@gmail.com > > <mailto:paullin3...@gmail.com> <mailto: > > paullin3...@gmail.com <mailto:paullin3...@gmail.com>> <mailto: > > paullin3...@gmail.com <mailto:paullin3...@gmail.com> <mailto: > > paullin3...@gmail.com <mailto:paullin3...@gmail.com>>>> wrote: > > > Hi Weihua, > > You’re right. Distributing the SQLs to the TMs is one of the > > challenging > > parts of this FLIP. > > Web submission is not enabled in application mode currently as > > you > > said, > > but it could be changed if we have good reasons. > > What do you think about introducing a distributed storage for > > SQL > > Gateway? > > > We could make use of Flink file systems [1] to distribute the > > SQL > > Gateway > > generated resources, that should solve the problem at its root > > cause. > > > Users could specify Flink-supported file systems to ship files. > > It’s > > only > > required when using SQL Gateway with K8s application mode. > > [1] > > > > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > < > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > > < > > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > < > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > > > < > > > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > < > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > > < > > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > < > > > > https://nightlies.apache.org/flink/flink-docs-stable/docs/deployment/filesystems/overview/ > > > > > > Best, > Paul Lam > > 2023年6月1日 13:55，Weihua Hu <huweihua....@gmail.com <mailto: > > huweihua....@gmail.com> <mailto: > > huweihua....@gmail.com <mailto:huweihua....@gmail.com>>> 写道： > > > Thanks Paul for your reply. > > SQLDriver looks good to me. > > 2. Do you mean a pass the SQL string a configuration or a > > program > > argument? > > > > I brought this up because we were unable to pass the SQL file > > to > > Flink > > using Kubernetes mode. > For DataStream/Python users, they need to prepare their images > > for > > the > > jars > > and dependencies. > But for SQL users, they can use a common image to run > > different > > SQL > > queries > > if there are no other udf requirements. > It would be great if the SQL query and image were not bound. > > Using strings is a way to decouple these, but just as you > > mentioned, > > it's > > not easy to pass complex SQL. > > use web submission > > AFAIK, we can not use web submission in the Application mode. > > Please > > correct me if I'm wrong. > > > Best, > Weihua > > > On Wed, May 31, 2023 at 9:37 PM Paul Lam < > > paullin3...@gmail.com > > <mailto:paullin3...@gmail.com> > > <mailto:paullin3...@gmail.com <mailto:paullin3...@gmail.com>>> > > wrote: > > > Hi Biao, > > Thanks for your comments! > > 1. Scope: is this FLIP only targeted for non-interactive > > Flink > > SQL > > jobs > > in > > Application mode? More specifically, if we use SQL > > client/gateway > > to > > execute some interactive SQLs like a SELECT query, can we > > ask > > flink > > to > > use > > Application mode to execute those queries after this FLIP? > > > Thanks for pointing it out. I think only DMLs would be > > executed > > via > > SQL > > Driver. > I'll add the scope to the FLIP. > > 2. Deployment: I believe in YARN mode, the implementation is > > trivial as > > we > > can ship files via YARN's tool easily but for K8s, things > > can > > be > > more > > complicated as Shengkai said. > > > > Your input is very informative. I’m thinking about using web > > submission, > > but it requires exposing the JobManager port which could also > > be > > a > > problem > > on K8s. > > Another approach is to explicitly require a distributed > > storage > > to > > ship > > files, > but we may need a new deployment executor for that. > > What do you think of these two approaches? > > 3. Serialization of SessionState: in SessionState, there are > > some > > unserializable fields > like > > org.apache.flink.table.resource.ResourceManager#userClassLoader. > > It > > may be worthwhile to add more details about the > > serialization > > part. > > > I agree. That’s a missing part. But if we use ExecNodeGraph > > as > > Shengkai > > mentioned, do we eliminate the need for serialization of > > SessionState? > > > Best, > Paul Lam > > 2023年5月31日 13:07，Biao Geng <biaoge...@gmail.com <mailto: > > biaoge...@gmail.com> <mailto: > > biaoge...@gmail.com <mailto:biaoge...@gmail.com>>> 写道： > > > Thanks Paul for the proposal!I believe it would be very > > useful > > for > > flink > > users. > After reading the FLIP, I have some questions: > 1. Scope: is this FLIP only targeted for non-interactive > > Flink > > SQL > > jobs > > in > > Application mode? More specifically, if we use SQL > > client/gateway > > to > > execute some interactive SQLs like a SELECT query, can we > > ask > > flink > > to > > use > > Application mode to execute those queries after this FLIP? > 2. Deployment: I believe in YARN mode, the implementation is > > trivial as > > we > > can ship files via YARN's tool easily but for K8s, things > > can > > be > > more > > complicated as Shengkai said. I have implemented a simple > > POC > > < > > > > > > > > > https://github.com/bgeng777/flink/commit/5b4338fe52ec343326927f0fc12f015dd22b1133 > > < > > > > https://github.com/bgeng777/flink/commit/5b4338fe52ec343326927f0fc12f015dd22b1133 > > > < > > > > > https://github.com/bgeng777/flink/commit/5b4338fe52ec343326927f0fc12f015dd22b1133 > > < > > > > https://github.com/bgeng777/flink/commit/5b4338fe52ec343326927f0fc12f015dd22b1133 > > > > > based on SQL client before(i.e. consider the SQL client > > which > > supports > > executing a SQL file as the SQL driver in this FLIP). One > > problem > > I > > have > > met is how do we ship SQL files ( or Job Graph) to the k8s > > side. > > Without > > such support, users have to modify the initContainer or > > rebuild > > a > > new > > K8s > > image every time to fetch the SQL file. Like the flink k8s > > operator, > > one > > workaround is to utilize the flink config(transforming the > > SQL > > file > > to > > a > > escaped string like Weihua mentioned) which will be > > converted > > to a > > ConfigMap but K8s has size limit of ConfigMaps(no larger > > than > > 1MB > > < > > https://kubernetes.io/docs/concepts/configuration/configmap/ > > < > > https://kubernetes.io/docs/concepts/configuration/configmap/> < > > https://kubernetes.io/docs/concepts/configuration/configmap/ < > > https://kubernetes.io/docs/concepts/configuration/configmap/>>>). > > Not > > sure > > if we have better solutions. > 3. Serialization of SessionState: in SessionState, there are > > some > > unserializable fields > like > > org.apache.flink.table.resource.ResourceManager#userClassLoader. > > It > > may be worthwhile to add more details about the > > serialization > > part. > > > Best, > Biao Geng > > Paul Lam <paullin3...@gmail.com <mailto: > > paullin3...@gmail.com > > > <mailto:paullin3...@gmail.com <mailto:paullin3...@gmail.com>>> > > 于2023年5月31日周三 11:49写道： > > > Hi Weihua, > > Thanks a lot for your input! Please see my comments inline. > > - Is SQLRunner the better name? We use this to run a SQL > > Job. > > (Not > > strong, > > the SQLDriver is fine for me) > > > I’ve thought about SQL Runner but picked SQL Driver for the > > following > > reasons FYI: > > 1. I have a PythonDriver doing the same job for PyFlink [1] > 2. Flink program's main class is sort of like Driver in > > JDBC > > which > > translates SQLs into > databases specific languages. > > In general, I’m +1 for SQL Driver and +0 for SQL Runner. > > - Could we run SQL jobs using SQL in strings? Otherwise, > > we > > need > > to > > prepare > > a SQL file in an image for Kubernetes application mode, > > which > > may > > be > > a > > bit > > cumbersome. > > > Do you mean a pass the SQL string a configuration or a > > program > > argument? > > > I thought it might be convenient for testing propose, but > > not > > recommended > > for production, > cause Flink SQLs could be complicated and involves lots of > > characters > > that > > need to escape. > > WDYT? > > - I noticed that we don't specify the SQLDriver jar in the > > "run-application" > > command. Does that mean we need to perform automatic > > detection > > in > > Flink? > > > Yes! It’s like running a PyFlink job with the following > > command: > > > ``` > ./bin/flink run \ > --pyModule table.word_count \ > --pyFiles examples/python/table > ``` > > The CLI determines if it’s a SQL job, if yes apply the SQL > > Driver > > automatically. > > > [1] > > > > > > > > > https://github.com/apache/flink/blob/master/flink-python/src/main/java/org/apache/flink/client/python/PythonDriver.java > > < > > > > https://github.com/apache/flink/blob/master/flink-python/src/main/java/org/apache/flink/client/python/PythonDriver.java > > > < > > > > > https://github.com/apache/flink/blob/master/flink-python/src/main/java/org/apache/flink/client/python/PythonDriver.java > > < > > > > https://github.com/apache/flink/blob/master/flink-python/src/main/java/org/apache/flink/client/python/PythonDriver.java > > > > > Best, > Paul Lam > > 2023年5月30日 21:56，Weihua Hu <huweihua....@gmail.com > > <mailto: > > huweihua....@gmail.com> <mailto: > > huweihua....@gmail.com>> 写道： > > > Thanks Paul for the proposal. > > +1 for this. It is valuable in improving ease of use. > > I have a few questions. > - Is SQLRunner the better name? We use this to run a SQL > > Job. > > (Not > > strong, > > the SQLDriver is fine for me) > - Could we run SQL jobs using SQL in strings? Otherwise, > > we > > need > > to > > prepare > > a SQL file in an image for Kubernetes application mode, > > which > > may > > be > > a > > bit > > cumbersome. > - I noticed that we don't specify the SQLDriver jar in the > > "run-application" > > command. Does that mean we need to perform automatic > > detection > > in > > Flink? > > > > Best, > Weihua > > > On Mon, May 29, 2023 at 7:24 PM Paul Lam < > > paullin3...@gmail.com > > <mailto:paullin3...@gmail.com <mailto:paullin3...@gmail.com>>> > > wrote: > > > Hi team, > > I’d like to start a discussion about FLIP-316 [1], which > > introduces > > a > > SQL > > driver as the > default main class for Flink SQL jobs. > > Currently, Flink SQL could be executed out of the box > > either > > via > > SQL > > Client/Gateway > or embedded in a Flink Java/Python program. > > However, each one has its drawback: > > - SQL Client/Gateway doesn’t support the application > > deployment > > mode > > [2] > > - Flink Java/Python program requires extra work to write > > a > > non-SQL > > program > > > Therefore, I propose adding a SQL driver to act as the > > default > > main > > class > > for SQL jobs. > Please see the FLIP docs for details and feel free to > > comment. > > Thanks! > > > [1] > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-316%3A+Introduce+SQL+Driver > > < > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-316:+Introduce+SQL+Driver > > > [2] https://issues.apache.org/jira/browse/FLINK-26541 < > https://issues.apache.org/jira/browse/FLINK-26541> > > Best, > Paul Lam > > > > > > >
