Thanks Bowen ~ I agree we should somehow categorize our connector parameters.
For type1, I’m already preparing a solution like the Confluent schema registry + Avro schema inference thing, so this may not be a problem in the near future. For type3, I have some questions: > "SELECT * FROM mykafka WHERE offset > 12pm yesterday” Where does the offset column come from, a virtual column from the table schema, you said that >They change almost every time a query starts and have nothing to do with metadata, thus should not be part of table definition/DDL But why you can reference it in the query, I’m confused for that, can you elaborate a little ? Best, Danny Chan 在 2020年3月11日 +0800 PM12:52,Bowen Li <bowenl...@gmail.com>,写道: > Thanks Danny for kicking off the effort > > The root cause of too much manual work is Flink DDL has mixed 3 types of > params together and doesn't handle each of them very well. Below are how I > categorize them and corresponding solutions in my mind: > > - type 1: Metadata of external data, like external endpoint/url, > username/pwd, schemas, formats. > > Such metadata are mostly already accessible in external system as long as > endpoints and credentials are provided. Flink can get it thru catalogs, but > we haven't had many catalogs yet and thus Flink just hasn't been able to > leverage that. So the solution should be building more catalogs. Such > params should be part of a Flink table DDL/definition, and not overridable > in any means. > > > - type 2: Runtime params, like jdbc connector's fetch size, elasticsearch > connector's bulk flush size. > > Such params don't affect query results, but affect how results are produced > (eg. fast or slow, aka performance) - they are essentially execution and > implementation details. They change often in exploration or development > stages, but not quite frequently in well-defined long-running pipelines. > They should always have default values and can be missing in query. They > can be part of a table DDL/definition, but should also be replaceable in a > query - *this is what table "hints" in FLIP-113 should cover*. > > > - type 3: Semantic params, like kafka connector's start offset. > > Such params affect query results - the semantics. They'd better be as > filter conditions in WHERE clause that can be pushed down. They change > almost every time a query starts and have nothing to do with metadata, thus > should not be part of table definition/DDL, nor be persisted in catalogs. > If they will, users should create views to keep such params around (note > this is different from variable substitution). > > > Take Flink-Kafka as an example. Once we get these params right, here're the > steps users need to do to develop and run a Flink job: > - configure a Flink ConfluentSchemaRegistry with url, username, and password > - run "SELECT * FROM mykafka WHERE offset > 12pm yesterday" (simplified > timestamp) in SQL CLI, Flink automatically retrieves all metadata of > schema, file format, etc and start the job > - users want to make the job read Kafka topic faster, so it goes as "SELECT > * FROM mykafka /* faster_read_key=value*/ WHERE offset > 12pm yesterday" > - done and satisfied, users submit it to production > > > Regarding "CREATE TABLE t LIKE with (k1=v1, k2=v2), I think it's a > nice-to-have feature, but not a strategically critical, long-term solution, > because > 1) It may seem promising at the current stage to solve the > too-much-manual-work problem, but that's only because Flink hasn't > leveraged catalogs well and handled the 3 types of params above properly. > Once we get the params types right, the LIKE syntax won't be that > important, and will be just an easier way to create tables without retyping > long fields like username and pwd. > 2) Note that only some rare type of catalog can store k-v property pair, so > table created this way often cannot be persisted. In the foreseeable > future, such catalog will only be HiveCatalog, and not everyone has a Hive > metastore. To be honest, without persistence, recreating tables every time > this way is still a lot of keyboard typing. > > Cheers, > Bowen > > On Tue, Mar 10, 2020 at 8:07 PM Kurt Young <ykt...@gmail.com> wrote: > > > If a specific connector want to have such parameter and read if out of > > configuration, then that's fine. > > If we are talking about a configuration for all kinds of sources, I would > > be super careful about that. > > It's true it can solve maybe 80% cases, but it will also make the left 20% > > feels weird. > > > > Best, > > Kurt > > > > > > On Wed, Mar 11, 2020 at 11:00 AM Jark Wu <imj...@gmail.com> wrote: > > > > > Hi Kurt, > > > > > > #3 Regarding to global offset: > > > I'm not saying to use the global configuration to override connector > > > properties by the planner. > > > But the connector should take this configuration and translate into their > > > client API. > > > AFAIK, almost all the message queues support eariliest and latest and a > > > timestamp value as start point. > > > So we can support 3 options for this configuration: "eariliest", "latest" > > > and a timestamp string value. > > > Of course, this can't solve 100% cases, but I guess can sovle 80% or 90% > > > cases. > > > And the remaining cases can be resolved by LIKE syntax which I guess is > > not > > > very common cases. > > > > > > Best, > > > Jark > > > > > > > > > On Wed, 11 Mar 2020 at 10:33, Kurt Young <ykt...@gmail.com> wrote: > > > > > > > Good to have such lovely discussions. I also want to share some of my > > > > opinions. > > > > > > > > #1 Regarding to error handling: I also think ignore invalid hints would > > > be > > > > dangerous, maybe > > > > the simplest solution is just throw an exception. > > > > > > > > #2 Regarding to property replacement: I don't think we should > > constraint > > > > ourself to > > > > the meaning of the word "hint", and forbidden it modifying any > > properties > > > > which can effect > > > > query results. IMO `PROPERTIES` is one of the table hints, and a > > powerful > > > > one. It can > > > > modify properties located in DDL's WITH block. But I also see the harm > > > that > > > > if we make it > > > > too flexible like change the kafka topic name with a hint. Such use > > case > > > is > > > > not common and > > > > sounds very dangerous to me. I would propose we have a map of hintable > > > > properties for each > > > > connector, and should validate all passed in properties are actually > > > > hintable. And combining with > > > > #1 error handling, we can throw an exception once received invalid > > > > property. > > > > > > > > #3 Regarding to global offset: I'm not sure it's feasible. Different > > > > connectors will have totally > > > > different properties to represent offset, some might be timestamps, > > some > > > > might be string literals > > > > like "earliest", and others might be just integers. > > > > > > > > Best, > > > > Kurt > > > > > > > > > > > > On Tue, Mar 10, 2020 at 11:46 PM Jark Wu <imj...@gmail.com> wrote: > > > > > > > > > Hi everyone, > > > > > > > > > > I want to jump in the discussion about the "dynamic start offset" > > > > problem. > > > > > First of all, I share the same concern with Timo and Fabian, that the > > > > > "start offset" affects the query semantics, i.e. the query result. > > > > > But "hints" is just used for optimization which should affect the > > > result? > > > > > > > > > > I think the "dynamic start offset" is an very important usability > > > problem > > > > > which will be faced by many streaming platforms. > > > > > I also agree "CREATE TEMPORARY TABLE Temp (LIKE t) WITH > > > > > ('connector.startup-timestamp-millis' = '1578538374471')" is verbose, > > > > what > > > > > if we have 10 tables to join? > > > > > > > > > > However, what I want to propose (should be another thread) is a > > global > > > > > configuration to reset start offsets of all the source connectors > > > > > in the query session, e.g. "table.sources.start-offset". This is > > > possible > > > > > now because `TableSourceFactory.Context` has `getConfiguration` > > > > > method to get the session configuration, and use it to create an > > > adapted > > > > > TableSource. > > > > > Then we can also expose to SQL CLI via SET command, e.g. `SET > > > > > 'table.sources.start-offset'='earliest';`, which is pretty simple and > > > > > straightforward. > > > > > > > > > > This is very similar to KSQL's `SET 'auto.offset.reset'='earliest'` > > > which > > > > > is very helpful IMO. > > > > > > > > > > Best, > > > > > Jark > > > > > > > > > > > > > > > On Tue, 10 Mar 2020 at 22:29, Timo Walther <twal...@apache.org> > > wrote: > > > > > > > > > > > Hi Danny, > > > > > > > > > > > > compared to the hints, FLIP-110 is fully compliant to the SQL > > > standard. > > > > > > > > > > > > I don't think that `CREATE TEMPORARY TABLE Temp (LIKE t) WITH > > (k=v)` > > > is > > > > > > too verbose or awkward for the power of basically changing the > > entire > > > > > > connector. Usually, this statement would just precede the query in > > a > > > > > > multiline file. So it can be change "in-place" like the hints you > > > > > proposed. > > > > > > > > > > > > Many companies have a well-defined set of tables that should be > > used. > > > > It > > > > > > would be dangerous if users can change the path or topic in a hint. > > > The > > > > > > catalog/catalog manager should be the entity that controls which > > > tables > > > > > > exist and how they can be accessed. > > > > > > > > > > > > > what’s the problem there if we user the table hints to support > > > > “start > > > > > > offset”? > > > > > > > > > > > > IMHO it violates the meaning of a hint. According to the > > dictionary, > > > a > > > > > > hint is "a statement that expresses indirectly what one prefers not > > > to > > > > > > say explicitly". But offsets are a property that are very explicit. > > > > > > > > > > > > If we go with the hint approach, it should be expressible in the > > > > > > TableSourceFactory which properties are supported for hinting. Or > > do > > > > you > > > > > > plan to offer those hints in a separate Map<String, String> that > > > cannot > > > > > > overwrite existing properties? I think this would be a different > > > > story... > > > > > > > > > > > > Regards, > > > > > > Timo > > > > > > > > > > > > > > > > > > On 10.03.20 10:34, Danny Chan wrote: > > > > > > > Thanks Timo ~ > > > > > > > > > > > > > > Personally I would say that offset > 0 and start offset = 10 does > > > not > > > > > > have the same semantic, so from the SQL aspect, we can not > > implement > > > a > > > > > > “starting offset” hint for query with such a syntax. > > > > > > > > > > > > > > And the CREATE TABLE LIKE syntax is a DDL which is just verbose > > for > > > > > > defining such dynamic parameters even if it could do that, shall we > > > > force > > > > > > users to define a temporal table for each query with dynamic > > params, > > > I > > > > > > would say it’s an awkward solution. > > > > > > > > > > > > > > "Hints should give "hints" but not affect the actual produced > > > > result.” > > > > > > You mentioned that multiple times and could we give a reason, > > what’s > > > > the > > > > > > problem there if we user the table hints to support “start offset” > > ? > > > > From > > > > > > my side I saw some benefits for that: > > > > > > > > > > > > > > > > > > > > > • It’s very convent to set up these parameters, the syntax is > > very > > > > much > > > > > > like the DDL definition > > > > > > > • It’s scope is very clear, right on the table it attathed > > > > > > > • It does not affect the table schema, which means in order to > > > > specify > > > > > > the offset, there is no need to define an offset column which is > > > weird > > > > > > actually, offset should never be a column, it’s more like a > > metadata > > > > or a > > > > > > start option. > > > > > > > > > > > > > > So in total, FLIP-110 uses the offset more like a Hive partition > > > > prune, > > > > > > we can do that if we have an offset column, but most of the case we > > > do > > > > > not > > > > > > define that, so there is actually no conflict or overlap. > > > > > > > > > > > > > > Best, > > > > > > > Danny Chan > > > > > > > 在 2020年3月10日 +0800 PM4:28,Timo Walther <twal...@apache.org>,写道: > > > > > > > > Hi Danny, > > > > > > > > > > > > > > > > shouldn't FLIP-110[1] solve most of the problems we have around > > > > > defining > > > > > > > > table properties more dynamically without manual schema work? > > Also > > > > > > > > offset definition is easier with such a syntax. They must not be > > > > > defined > > > > > > > > in catalog but could be temporary tables that extend from the > > > > original > > > > > > > > table. > > > > > > > > > > > > > > > > In general, we should aim to keep the syntax concise and don't > > > > provide > > > > > > > > too many ways of doing the same thing. Hints should give "hints" > > > but > > > > > not > > > > > > > > affect the actual produced result. > > > > > > > > > > > > > > > > Some connector properties might also change the plan or schema > > in > > > > the > > > > > > > > future. E.g. they might also define whether a table source > > > supports > > > > > > > > certain push-downs (e.g. predicate push-down). > > > > > > > > > > > > > > > > Dawid is currently working a draft that might makes it possible > > to > > > > > > > > expose a Kafka offset via the schema such that `SELECT * FROM > > > Topic > > > > > > > > WHERE offset > 10` would become possible and could be pushed > > down. > > > > But > > > > > > > > this is of course, not planned initially. > > > > > > > > > > > > > > > > Regards, > > > > > > > > Timo > > > > > > > > > > > > > > > > > > > > > > > > [1] > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-110%3A+Support+LIKE+clause+in+CREATE+TABLE > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On 10.03.20 08:34, Danny Chan wrote: > > > > > > > > > Thanks Wenlong ~ > > > > > > > > > > > > > > > > > > For PROPERTIES Hint Error handling > > > > > > > > > > > > > > > > > > Actually we have no way to figure out whether a error prone > > hint > > > > is a > > > > > > PROPERTIES hint, for example, if use writes a hint like > > ‘PROPERTIAS’, > > > > we > > > > > do > > > > > > not know if this hint is a PROPERTIES hint, what we know is that > > the > > > > hint > > > > > > name was not registered in our Flink. > > > > > > > > > > > > > > > > > > If the user writes the hint name correctly (i.e. PROPERTIES), > > we > > > > did > > > > > > can enforce the validation of the hint options though the pluggable > > > > > > HintOptionChecker. > > > > > > > > > > > > > > > > > > For PROPERTIES Hint Option Format > > > > > > > > > > > > > > > > > > For a key value style hint option, the key can be either a > > simple > > > > > > identifier or a string literal, which means that it’s compatible > > with > > > > our > > > > > > DDL syntax. We support simple identifier because many other hints > > do > > > > not > > > > > > have the component complex keys like the table properties, and we > > > want > > > > to > > > > > > unify the parse block. > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > Danny Chan > > > > > > > > > 在 2020年3月10日 +0800 PM3:19,wenlong.lwl <wenlong88....@gmail.com > > > > > ,写道: > > > > > > > > > > Hi Danny, thanks for the proposal. +1 for adding table > > > > > > > > > > hints, > > it > > > > is > > > > > > really > > > > > > > > > > a necessary feature for flink sql to integrate with a > > > > > > > > > > catalog. > > > > > > > > > > > > > > > > > > > > For error handling, I think it would be more natural to > > > > > > > > > > throw > > an > > > > > > > > > > exception when error table hint provided, because the > > properties > > > > in > > > > > > hint > > > > > > > > > > will be merged and used to find the table factory which > > > > > > > > > > would > > > > cause > > > > > an > > > > > > > > > > exception when error properties provided, right? On the > > > > > > > > > > other > > > > hand, > > > > > > unlike > > > > > > > > > > other hints which just affect the way to execute the query, > > the > > > > > > property > > > > > > > > > > table hint actually affects the result of the query, we > > > > > > > > > > should > > > > never > > > > > > ignore > > > > > > > > > > the given property hints. > > > > > > > > > > > > > > > > > > > > For the format of property hints, currently, in sql client, > > > > > > > > > > we > > > > > accept > > > > > > > > > > properties in format of string only in DDL: > > > > > 'connector.type'='kafka', > > > > > > I > > > > > > > > > > think the format of properties in hint should be the same as > > the > > > > > > format we > > > > > > > > > > defined in ddl. What do you think? > > > > > > > > > > > > > > > > > > > > Bests, > > > > > > > > > > Wenlong Lyu > > > > > > > > > > > > > > > > > > > > On Tue, 10 Mar 2020 at 14:22, Danny Chan < > > yuzhao....@gmail.com> > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > To Weike: About the Error Handing > > > > > > > > > > > > > > > > > > > > > > To be consistent with other SQL vendors, the default is to > > log > > > > > > warnings > > > > > > > > > > > and if there is any error (invalid hint name or options), > > > > > > > > > > > the > > > > hint > > > > > > is just > > > > > > > > > > > ignored. I have already addressed in the wiki. > > > > > > > > > > > > > > > > > > > > > > To Timo: About the PROPERTIES Table Hint > > > > > > > > > > > > > > > > > > > > > > • The properties hints is also optional, user can pass in > > > > > > > > > > > an > > > > option > > > > > > to > > > > > > > > > > > override the table properties but this does not mean it is > > > > > required. > > > > > > > > > > > • They should not include semantics: does the properties > > belong > > > > to > > > > > > > > > > > semantic ? I don't think so, the plan does not change > > > > > > > > > > > right ? > > > The > > > > > > result > > > > > > > > > > > set may be affected, but there are already some hints do > > > > > > > > > > > so, > > > for > > > > > > example, > > > > > > > > > > > MS-SQL MAXRECURSION and SNAPSHOT hint [1] > > > > > > > > > > > • `SELECT * FROM t(k=v, k=v)`: this grammar breaks the SQL > > > > standard > > > > > > > > > > > compared to the hints way(which is included in comments) > > > > > > > > > > > • I actually didn't found any vendors to support such > > grammar, > > > > and > > > > > > there > > > > > > > > > > > is no way to override table level properties dynamically. > > > > > > > > > > > For > > > > > normal > > > > > > RDBMS, > > > > > > > > > > > I think there are no requests for such dynamic parameters > > > because > > > > > > all the > > > > > > > > > > > table have the same storage and computation and they are > > almost > > > > all > > > > > > batch > > > > > > > > > > > tables. > > > > > > > > > > > • While Flink as a computation engine has many connectors, > > > > > > especially for > > > > > > > > > > > some message queue like Kafka, we would have a > > > > > > > > > > > start_offset > > > which > > > > > is > > > > > > > > > > > different each time we start the query, such parameters > > > > > > > > > > > can > > not > > > > be > > > > > > > > > > > persisted to catalog, because it’s not static, this is > > actually > > > > the > > > > > > > > > > > background we propose the table hints to indicate such > > > properties > > > > > > > > > > > dynamically. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > To Jark and Jinsong: I have removed the query hints part > > > > > > > > > > > and > > > > change > > > > > > the > > > > > > > > > > > title. > > > > > > > > > > > > > > > > > > > > > > [1] > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://docs.microsoft.com/en-us/sql/t-sql/queries/hints-transact-sql-query?view=sql-server-ver15 > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > Danny Chan > > > > > > > > > > > 在 2020年3月9日 +0800 PM5:46,Timo Walther <twal...@apache.org > > > ,写道: > > > > > > > > > > > > Hi Danny, > > > > > > > > > > > > > > > > > > > > > > > > thanks for the proposal. I agree with Jark and Jingsong. > > > Planner > > > > > > hints > > > > > > > > > > > > and table hints are orthogonal topics that should be > > discussed > > > > > > > > > > > separately. > > > > > > > > > > > > > > > > > > > > > > > > I share Jingsong's opinion that we should not use > > > > > > > > > > > > planner > > > hints > > > > > for > > > > > > > > > > > > passing connector properties. Planner hints should be > > optional > > > > at > > > > > > any > > > > > > > > > > > > time. They should not include semantics but only affect > > > > execution > > > > > > time. > > > > > > > > > > > > Connector properties are an important part of the query > > > itself. > > > > > > > > > > > > > > > > > > > > > > > > Have you thought about options such as `SELECT * FROM > > > > > > > > > > > > t(k=v, > > > > > k=v)`? > > > > > > How > > > > > > > > > > > > are other vendors deal with this problem? > > > > > > > > > > > > > > > > > > > > > > > > Regards, > > > > > > > > > > > > Timo > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On 09.03.20 10:37, Jingsong Li wrote: > > > > > > > > > > > > > Hi Danny, +1 for table hints, thanks for driving. > > > > > > > > > > > > > > > > > > > > > > > > > > I took a look to FLIP, most of content are talking > > > > > > > > > > > > > about > > > query > > > > > > hints. > > > > > > > > > > > It is > > > > > > > > > > > > > hard to discussion and voting. So +1 to split it as > > > > > > > > > > > > > Jark > > > said. > > > > > > > > > > > > > > > > > > > > > > > > > > Another thing is configuration that suitable to > > > > > > > > > > > > > config with > > > > table > > > > > > > > > > > hints: > > > > > > > > > > > > > "connector.path" and "connector.topic", Are they > > > > > > > > > > > > > really > > > > suitable > > > > > > for > > > > > > > > > > > table > > > > > > > > > > > > > hints? Looks weird to me. Because I think these > > > > > > > > > > > > > properties > > > are > > > > > the > > > > > > > > > > > core of > > > > > > > > > > > > > table. > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > > > Jingsong Lee > > > > > > > > > > > > > > > > > > > > > > > > > > On Mon, Mar 9, 2020 at 5:30 PM Jark Wu > > > > > > > > > > > > > <imj...@gmail.com> > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks Danny for starting the discussion. > > > > > > > > > > > > > > +1 for this feature. > > > > > > > > > > > > > > > > > > > > > > > > > > > > If we just focus on the table hints not the query > > > > > > > > > > > > > > hints in > > > > this > > > > > > > > > > > release, > > > > > > > > > > > > > > could you split the FLIP into two FLIPs? > > > > > > > > > > > > > > Because it's hard to vote on partial part of a > > > > > > > > > > > > > > FLIP. You > > can > > > > > keep > > > > > > > > > > > the table > > > > > > > > > > > > > > hints proposal in FLIP-113 and move query hints into > > another > > > > > FLIP. > > > > > > > > > > > > > > So that we can focuse on the table hints in the > > > > > > > > > > > > > > FLIP. > > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > Jark > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Mon, 9 Mar 2020 at 17:14, DONG, Weike < > > > > > kyled...@connect.hku.hk > > > > > > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Hi Danny, > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > This is a nice feature, +1. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > One thing I am interested in but not mentioned in > > > > > > > > > > > > > > > the > > > > proposal > > > > > is > > > > > > > > > > > the > > > > > > > > > > > > > > error > > > > > > > > > > > > > > > handling, as it is quite common for users to write > > > > > inappropriate > > > > > > > > > > > hints in > > > > > > > > > > > > > > > SQL code, if illegal or "bad" hints are given, > > > > > > > > > > > > > > > would the > > > > system > > > > > > > > > > > simply > > > > > > > > > > > > > > > ignore them or throw exceptions? > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Thanks : ) > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > > > > > Weike > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Mon, Mar 9, 2020 at 5:02 PM Danny Chan < > > > > > yuzhao....@gmail.com> > > > > > > > > > > > wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Note: > > > > > > > > > > > > > > > > we only plan to support table hints in Flink > > > > > > > > > > > > > > > > release > > 1.11, > > > > so > > > > > > > > > > > please > > > > > > > > > > > > > > > focus > > > > > > > > > > > > > > > > mainly on the table hints part and just ignore > > > > > > > > > > > > > > > > the > > planner > > > > > > > > > > > hints, sorry > > > > > > > > > > > > > > > for > > > > > > > > > > > > > > > > that mistake ~ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > > > > > > Danny Chan > > > > > > > > > > > > > > > > 在 2020年3月9日 +0800 PM4:36,Danny Chan < > > yuzhao....@gmail.com > > > > > > ,写道: > > > > > > > > > > > > > > > > > Hi, fellows ~ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I would like to propose the supports for SQL > > > > > > > > > > > > > > > > > hints for > > > our > > > > > > > > > > > Flink SQL. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > We would support hints syntax as following: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > select /*+ NO_HASH_JOIN, RESOURCE(mem='128mb', > > > > > > > > > > > parallelism='24') */ > > > > > > > > > > > > > > > > > from > > > > > > > > > > > > > > > > > emp /*+ INDEX(idx1, idx2) */ > > > > > > > > > > > > > > > > > join > > > > > > > > > > > > > > > > > dept /*+ PROPERTIES(k1='v1', k2='v2') */ > > > > > > > > > > > > > > > > > on > > > > > > > > > > > > > > > > > emp.deptno = dept.deptno > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Basically we would support both query > > > > > > > > > > > > > > > > > hints(after the > > > > SELECT > > > > > > > > > > > keyword) > > > > > > > > > > > > > > > > and table hints(after the referenced table > > > > > > > > > > > > > > > > name), for > > > 1.11, > > > > we > > > > > > > > > > > plan to > > > > > > > > > > > > > > > only > > > > > > > > > > > > > > > > support table hints with a hint probably named > > PROPERTIES: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > table_name /*+ PROPERTIES(k1='v1', k2='v2') > > > > > > > > > > > > > > > > > *+/ > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I am looking forward to your comments. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > You can access the FLIP here: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > https://cwiki.apache.org/confluence/display/FLINK/FLIP-113%3A+SQL+and+Planner+Hints > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Best, > > > > > > > > > > > > > > > > > Danny Chan > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >