Hi Jiabao, Yes, I still have concerns.
The FLIP violates the following two principles regarding configuration: 1.* A config of a class should never negate the semantic of a decorative interface implemented by that class. * A decorative interface is a public contract with other components, while a config is only internal to the class itself. The configurations for the Sources are not (and should never be) visible or understood to other components (e.g. optimizer). A configuration of a Source only controls the behavior of that Source, provided it is not violating the API contract / semantic defined by the decorative interface. So when a Source implementation implements SupportsFilterPushdown, this is a clear public contract with Flink that filters should be pushed down to that Source. Therefore, for the same source, there should not be a configuration "source.filter-push-down.enabled" which stops the filters from being pushed down to that Source. However, that specific source implementation can have its own config to control its internal behavior, e.g. "ignore-pushed-down-filters.enabled" which may push back all the pushed down filters back to the Flink optimizer. 2. When we are talking about "common configs", in fact we are talking about "configs for common (abstract) implementation classes". With that as a context, *a common config should always be backed by a common implementation class, so that consistent behavior can be guaranteed. * The LookupOptions you mentioned are configurations defined for classes DefaultLookupCache / PeriodicCacheReloadTrigger / TimedCacheReloadTrigger. These configs are considered as "common" only because the implementation classes using them are common building blocks for lookup table implementations. It would not make sense to have a dangling config in the LookupOptions without the underlying common implementation class, but only relies on a specific source to implement the stated behavior. As a bad example, there is this outlier config "max-retries" in LookupOptions, which I don't think should be here. This is because the retry behavior can be very implementation specific. For example, there can be many different flavors of retry related configurations, retry-backoff, retry-timeout, retry-async, etc. Why only max-retry is put here? should all of them be put here? If we put all such kinds of configs in the common configs for "standardization and unification", the number of "common configs" can easily go crazy. And I don't see material benefits of doing that. So here I don't think the configuration "max-retry" should be in LookupOptions, because it is not backed by any common implementation classes. If max-retry is implemented in the HBase source, it should stay there. For the same reason, the config proposed in this FLIP (probably with a name less confusing for the first reason mentioned above) should stay in the specific Source implementation. For the two reasons above, I am -1 to what the FLIP currently proposes. I think the right way to address the motivation here is still to have a config like "ignore-pushed-down-filters.enabled" for the specific source implementation. Please let me know if this solves the problem you are facing. Thanks, Jiangjie (Becket) Qin On Wed, Nov 15, 2023 at 11:52 AM Jiabao Sun <jiabao....@xtransfer.cn.invalid> wrote: > Hi Becket, > > The purpose of introducing this configuration is that not all filter > pushdowns can improve overall performance. > If the filter can hit the external index, then pushdown is definitely > worth it, as it can not only improve query time but also decrease network > overhead. > However, for filters that do not hit the external index, it may increase a > lot of performance overhead on the external system. > > Undeniably, if the connector can make accurate decisions for good and bad > filters, we may not need to introduce this configuration option to disable > pushing down filters to the external system. > However, it is currently not easy to achieve. > > IMO, supporting filter pushdown does not mean that always filter pushdown > is better. > In the absence of automatic decision-making, I think we should leave this > decision to users. > > The newly introduced configuration option is similar to LookupOptions, > providing unified naming and default values to avoid confusion caused by > inconsistent naming in different connectors for users. > Setting the default value to true allows it to maintain compatibility with > the default behavior of "always pushdown". > > Do you have any other concerns about this proposal? Please let me know. > > Thanks, > Jiabao > > > > 2023年10月31日 17:29，Jiabao Sun <jiabao....@xtransfer.cn.INVALID> 写道： > > > > Hi Becket, > > > > Actually, for FileSystemSource, it is not always desired, only OCR file > formats support filter pushdown. > > > > We can disable predicate pushdown for FileSystemSource by setting > 'table.optimizer.source.predicate-pushdown-enabled' to false. > > I think we can also disable filter pushdown at a more granular level > through fine-grained configuration. > > > > > > Best, > > Jiabao > > > > > >> 2023年10月31日 16:50，Becket Qin <becket....@gmail.com> 写道： > >> > >> Hi Jiabao, > >> > >> Thanks for the explanation. Maybe it's easier to explain with an > example. > >> > >> Let's take FileSystemTableSource as an example. Currently it implements > >> SupportsFilterPushDown interface. With your proposal, does it have to > >> support `source.filter-push-down.enabled` as well? But this > configuration > >> does not quite make sense for the FileSystemTableSource because filter > >> pushdown is always desired. However, because this configuration is a > part > >> of the SupportsFilterPushDown interface (which sounds confusing to begin > >> with), the FileSystemTableSource can only do one of the following: > >> > >> 1. Ignore the user configuration to always apply the pushed down > filters - > >> this is an apparent anti-pattern because a configuration should always > do > >> what it says. > >> 2. Throw an exception telling users that this configuration is not > >> applicable to the FileSystemTableSource. > >> 3. Implement this configuration to push back the pushed down filters, > even > >> though this is never desired. > >> > >> None of the above options looks awkward. I am curious what your > solution is > >> here? > >> > >> Thanks, > >> > >> Jiangjie (Becket) Qin > >> > >> On Tue, Oct 31, 2023 at 3:11 PM Jiabao Sun <jiabao....@xtransfer.cn > .invalid> > >> wrote: > >> > >>> Thanks Becket for the further explanation. > >>> > >>> Perhaps I didn't explain it clearly. > >>> > >>> 1. If a source does not implement the SupportsFilterPushDown interface, > >>> the newly added configurations do not need to be added to either the > >>> requiredOptions or optionalOptions. > >>> Similar to LookupOptions, if a source does not implement > >>> LookupTableSource, there is no need to add LookupOptions to either > >>> requiredOptions or optionalOptions. > >>> > >>> 2. "And these configs are specific to those sources, instead of common > >>> configs." > >>> The newly introduced configurations define standardized names and > default > >>> values. > >>> They still belong to the configuration at the individual source level. > >>> The purpose is to avoid scattered configuration items when different > >>> sources implement the same logic. > >>> Whether a source should accept these configurations is determined by > the > >>> source's Factory. > >>> > >>> Best, > >>> Jiabao > >>> > >>> > >>>> 2023年10月31日 13:47，Becket Qin <becket....@gmail.com> 写道： > >>>> > >>>> Hi Jiabao, > >>>> > >>>> Please see the replies inline. > >>>> > >>>> Introducing common configurations does not mean that all sources must > >>>>> accept these configuration options. > >>>>> The configuration options supported by a source are determined by the > >>>>> requiredOptions and optionalOptions in the Factory interface. > >>>> > >>>> This is not true. Both required and optional options are SUPPORTED. > That > >>>> means they are implemented and if one specifies an optional config it > >>> will > >>>> still take effect. An OptionalConfig is "Optional" because this > >>>> configuration has a default value. Hence, it is OK that users do not > >>>> specify their own value. In another word, it is "optional" for the end > >>>> users to set the config, but the implementation and support for that > >>> config > >>>> is NOT optional. In case a source does not support a common config, an > >>>> exception must be thrown when the config is provided by the end users. > >>>> However, the config we are talking about in this FLIP is a common > config > >>>> optional to implement, meaning that sometimes the claimed behavior > won't > >>> be > >>>> there even if users specify that config. > >>>> > >>>> Similar to sources that do not implement the LookupTableSource > interface, > >>>>> sources that do not implement the SupportsFilterPushDown interface > also > >>> do > >>>>> not need to accept newly introduced options. > >>>> > >>>> First of all, filter pushdown is a behavior of the query optimizer, > not > >>> the > >>>> behavior of Sources. The Sources tells the optimizer that it has the > >>>> ability to accept pushed down filters by implementing the > >>>> SupportsFilterPushDown interface. And this is the only contract > between > >>> the > >>>> Source and Optimizer regarding whether filters should be pushed down. > As > >>>> long as a specific source implements this decorative interface, filter > >>>> pushdown should always take place, i.e. > >>>> *SupportsFilterPushDown.applyFilters()* will be called. There should > be > >>> no > >>>> other config to disable that call. However, Sources can decide how to > >>>> behave based on their own configurations after *applyFilters()* is > >>> called. > >>>> And these configs are specific to those sources, instead of common > >>> configs. > >>>> Please see the examples I mentioned in the previous email. > >>>> > >>>> Thanks, > >>>> > >>>> Jiangjie (Becket) Qin > >>>> > >>>> On Tue, Oct 31, 2023 at 10:27 AM Jiabao Sun <jiabao....@xtransfer.cn > >>> .invalid> > >>>> wrote: > >>>> > >>>>> Hi Becket, > >>>>> > >>>>> Sorry, there was a typo in the second point. Let me correct it: > >>>>> > >>>>> Introducing common configurations does not mean that all sources must > >>>>> accept these configuration options. > >>>>> The configuration options supported by a source are determined by the > >>>>> requiredOptions and optionalOptions in the Factory interface. > >>>>> > >>>>> Similar to sources that do not implement the LookupTableSource > >>> interface, > >>>>> sources that do not implement the SupportsFilterPushDown interface > also > >>> do > >>>>> not need to accept newly introduced options. > >>>>> > >>>>> Best, > >>>>> Jiabao > >>>>> > >>>>> > >>>>>> 2023年10月31日 10:13，Jiabao Sun <jiabao....@xtransfer.cn.INVALID> 写道： > >>>>>> > >>>>>> Thanks Becket for the feedback. > >>>>>> > >>>>>> 1. Currently, the SupportsFilterPushDown#applyFilters method > returns a > >>>>> result that includes acceptedFilters and remainingFilters. The source > >>> can > >>>>> decide to push down some filters or not accept any of them. > >>>>>> 2. Introducing common configuration options does not mean that a > source > >>>>> that supports the SupportsFilterPushDown capability must accept this > >>>>> configuration. Similar to LookupOptions, only sources that implement > the > >>>>> LookupTableSource interface are necessary to accept these > configuration > >>>>> options. > >>>>>> > >>>>>> Best, > >>>>>> Jiabao > >>>>>> > >>>>>> > >>>>>>> 2023年10月31日 07:49，Becket Qin <becket....@gmail.com> 写道： > >>>>>>> > >>>>>>> Hi Jiabao and Ruanhang, > >>>>>>> > >>>>>>> Adding a configuration of source.filter-push-down.enabled as a > common > >>>>>>> source configuration seems problematic. > >>>>>>> 1. The config name is misleading. filter pushdown should only be > >>>>> determined > >>>>>>> by whether the SupportsFilterPushdown interface is implemented or > not. > >>>>>>> 2. The behavior of this configuration is only applicable to some > >>> source > >>>>>>> implementations. Why is it a common configuration? > >>>>>>> > >>>>>>> Here's my suggestion for design principles: > >>>>>>> 1. Only add source impl specific configuration to corresponding > >>> sources. > >>>>>>> 2. The configuration name should not overrule existing common > >>> contracts. > >>>>>>> > >>>>>>> For example, in the case of MySql source. There are several > options: > >>>>>>> 1. Have a configuration of `*mysql.avoid.remote.full.table.scan`*. > If > >>>>> this > >>>>>>> configuration is set, and a filter pushdown does not hit an index, > the > >>>>>>> MySql source impl would not further pushdown the filter to MySql > >>>>> servers. > >>>>>>> Note that this assumes the MySql source can retrieve the index > >>>>> information > >>>>>>> from the MySql servers. > >>>>>>> 2. If the MySql index information is not available to the MySql > >>> source, > >>>>> the > >>>>>>> configuration could be something like > >>>>> *`mysql.pushback.pushed.down.filters`*. > >>>>>>> Once set to true, MySql source would just add all the filters to > the > >>>>>>> RemainingFilters in the Result returned by > >>>>>>> *SupportsFilterPushdown.applyFilters().* > >>>>>>> 3. An alternative to option 2 is to have a ` > >>>>>>> *mysql.apply.predicates.after.scan*`. When it is set to true, MySql > >>>>> source > >>>>>>> will not push the filter down to the MySql servers, but apply the > >>>>> filters > >>>>>>> inside the MySql source itself. > >>>>>>> > >>>>>>> As you may see, the above configurations do not disable filter > >>> pushdown > >>>>>>> itself. They just allow various implementations of filter pushdown. > >>> And > >>>>> the > >>>>>>> configuration name does not give any illusion that filter pushdown > is > >>>>>>> disabled. > >>>>>>> > >>>>>>> Thanks, > >>>>>>> > >>>>>>> Jiangjie (Becket) Qin > >>>>>>> > >>>>>>> On Mon, Oct 30, 2023 at 11:58 PM Jiabao Sun < > jiabao....@xtransfer.cn > >>>>> .invalid> > >>>>>>> wrote: > >>>>>>> > >>>>>>>> Thanks Hang for the suggestion. > >>>>>>>> > >>>>>>>> > >>>>>>>> I think the configuration of TableSource is not closely related to > >>>>>>>> SourceReader, > >>>>>>>> so I prefer to introduce a independent configuration class > >>>>>>>> TableSourceOptions in the flink-table-common module, similar to > >>>>>>>> LookupOptions. > >>>>>>>> > >>>>>>>> For the second point, I suggest adding Java doc to the > >>>>> SupportsXXXPushDown > >>>>>>>> interfaces, providing detailed information on these options that > >>> needs > >>>>> to > >>>>>>>> be supported. > >>>>>>>> > >>>>>>>> I have made updates in the FLIP document. > >>>>>>>> Please help check it again. > >>>>>>>> > >>>>>>>> > >>>>>>>> Best, > >>>>>>>> Jiabao > >>>>>>>> > >>>>>>>> > >>>>>>>>> 2023年10月30日 17:23，Hang Ruan <ruanhang1...@gmail.com> 写道： > >>>>>>>>> > >>>>>>>>> Thanks for the improvements, Jiabao. > >>>>>>>>> > >>>>>>>>> There are some details that I am not sure about. > >>>>>>>>> 1. The new option `source.filter-push-down.enabled` will be > added to > >>>>>>>> which > >>>>>>>>> class? I think it should be `SourceReaderOptions`. > >>>>>>>>> 2. How are the connector developers able to know and follow the > >>> FLIP? > >>>>> Do > >>>>>>>> we > >>>>>>>>> need an abstract base class or provide a default method? > >>>>>>>>> > >>>>>>>>> Best, > >>>>>>>>> Hang > >>>>>>>>> > >>>>>>>>> Jiabao Sun <jiabao....@xtransfer.cn.invalid> 于2023年10月30日周一 > >>> 14:45写道： > >>>>>>>>> > >>>>>>>>>> Hi, all, > >>>>>>>>>> > >>>>>>>>>> Thanks for the lively discussion. > >>>>>>>>>> > >>>>>>>>>> Based on the discussion, I have made some adjustments to the > FLIP > >>>>>>>> document: > >>>>>>>>>> > >>>>>>>>>> 1. The name of the newly added option has been changed to > >>>>>>>>>> "source.filter-push-down.enabled". > >>>>>>>>>> 2. Considering compatibility with older versions, the newly > added > >>>>>>>>>> "source.filter-push-down.enabled" option needs to respect the > >>>>>>>> optimizer's > >>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" option. > >>>>>>>>>> But there is a consideration to remove the old option in Flink > 2.0. > >>>>>>>>>> 3. We can provide more options to disable other source abilities > >>> with > >>>>>>>> side > >>>>>>>>>> effects, such as “source.aggregate.enabled” and > >>>>>>>> “source.projection.enabled" > >>>>>>>>>> This is not urgent and can be continuously introduced. > >>>>>>>>>> > >>>>>>>>>> Looking forward to your feedback again. > >>>>>>>>>> > >>>>>>>>>> Best, > >>>>>>>>>> Jiabao > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>>>>> 2023年10月29日 08:45，Becket Qin <becket....@gmail.com> 写道： > >>>>>>>>>>> > >>>>>>>>>>> Thanks for digging into the git history, Jark. I agree it makes > >>>>> sense > >>>>>>>> to > >>>>>>>>>>> deprecate this API in 2.0. > >>>>>>>>>>> > >>>>>>>>>>> Cheers, > >>>>>>>>>>> > >>>>>>>>>>> Jiangjie (Becket) Qin > >>>>>>>>>>> > >>>>>>>>>>> On Fri, Oct 27, 2023 at 5:47 PM Jark Wu <imj...@gmail.com> > wrote: > >>>>>>>>>>> > >>>>>>>>>>>> Hi Becket, > >>>>>>>>>>>> > >>>>>>>>>>>> I checked the history of " > >>>>>>>>>>>> *table.optimizer.source.predicate-pushdown-enabled*", > >>>>>>>>>>>> it seems it was introduced since the legacy > FilterableTableSource > >>>>>>>>>>>> interface > >>>>>>>>>>>> which might be an experiential feature at that time. I don't > see > >>>>> the > >>>>>>>>>>>> necessity > >>>>>>>>>>>> of this option at the moment. Maybe we can deprecate this > option > >>>>> and > >>>>>>>>>> drop > >>>>>>>>>>>> it > >>>>>>>>>>>> in Flink 2.0[1] if it is not necessary anymore. This may help > to > >>>>>>>>>>>> simplify this discussion. > >>>>>>>>>>>> > >>>>>>>>>>>> > >>>>>>>>>>>> Best, > >>>>>>>>>>>> Jark > >>>>>>>>>>>> > >>>>>>>>>>>> [1]: https://issues.apache.org/jira/browse/FLINK-32383 > >>>>>>>>>>>> > >>>>>>>>>>>> > >>>>>>>>>>>> > >>>>>>>>>>>> On Thu, 26 Oct 2023 at 10:14, Becket Qin < > becket....@gmail.com> > >>>>>>>> wrote: > >>>>>>>>>>>> > >>>>>>>>>>>>> Thanks for the proposal, Jiabao. My two cents below: > >>>>>>>>>>>>> > >>>>>>>>>>>>> 1. If I understand correctly, the motivation of the FLIP is > >>>>> mainly to > >>>>>>>>>>>>> make predicate pushdown optional on SOME of the Sources. If > so, > >>>>>>>>>> intuitively > >>>>>>>>>>>>> the configuration should be Source specific instead of > general. > >>>>>>>>>> Otherwise, > >>>>>>>>>>>>> we will end up with general configurations that may not take > >>>>> effect > >>>>>>>> for > >>>>>>>>>>>>> some of the Source implementations. This violates the basic > rule > >>>>> of a > >>>>>>>>>>>>> configuration - it does what it says, regardless of the > >>>>>>>> implementation. > >>>>>>>>>>>>> While configuration standardization is usually a good thing, > it > >>>>>>>> should > >>>>>>>>>> not > >>>>>>>>>>>>> break the basic rules. > >>>>>>>>>>>>> If we really want to have this general configuration, for the > >>>>> sources > >>>>>>>>>>>>> this configuration does not apply, they should throw an > >>> exception > >>>>> to > >>>>>>>>>> make > >>>>>>>>>>>>> it clear that this configuration is not supported. However, > that > >>>>>>>> seems > >>>>>>>>>> ugly. > >>>>>>>>>>>>> > >>>>>>>>>>>>> 2. I think the actual motivation of this FLIP is about "how a > >>>>> source > >>>>>>>>>>>>> should implement predicate pushdown efficiently", not > "whether > >>>>>>>>>> predicate > >>>>>>>>>>>>> pushdown should be applied to the source." For example, if a > >>>>> source > >>>>>>>>>> wants > >>>>>>>>>>>>> to avoid additional computing load in the external system, it > >>> can > >>>>>>>>>> always > >>>>>>>>>>>>> read the entire record and apply the predicates by itself. > >>>>> However, > >>>>>>>>>> from > >>>>>>>>>>>>> the Flink perspective, the predicate pushdown is applied, it > is > >>>>> just > >>>>>>>>>>>>> implemented differently by the source. So the design > principle > >>>>> here > >>>>>>>> is > >>>>>>>>>> that > >>>>>>>>>>>>> Flink only cares about whether a source supports predicate > >>>>> pushdown > >>>>>>>> or > >>>>>>>>>> not, > >>>>>>>>>>>>> it does not care about the implementation efficiency / side > >>>>> effect of > >>>>>>>>>> the > >>>>>>>>>>>>> predicates pushdown. It is the Source implementation's > >>>>> responsibility > >>>>>>>>>> to > >>>>>>>>>>>>> ensure the predicates pushdown is implemented efficiently and > >>> does > >>>>>>>> not > >>>>>>>>>>>>> impose excessive pressure on the external system. And it is > OK > >>> to > >>>>>>>> have > >>>>>>>>>>>>> additional configurations to achieve this goal. Obviously, > such > >>>>>>>>>>>>> configurations will be source specific in this case. > >>>>>>>>>>>>> > >>>>>>>>>>>>> 3. Regarding the existing configurations of > >>>>>>>>>> *table.optimizer.source.predicate-pushdown-enabled. > >>>>>>>>>>>>> *I am not sure why we need it. Supposedly, if a source > >>> implements > >>>>> a > >>>>>>>>>>>>> SupportsXXXPushDown interface, the optimizer should push the > >>>>>>>>>> corresponding > >>>>>>>>>>>>> predicates to the Source. I am not sure in which case this > >>>>>>>>>> configuration > >>>>>>>>>>>>> would be used. Any ideas @Jark Wu <imj...@gmail.com>? > >>>>>>>>>>>>> > >>>>>>>>>>>>> Thanks, > >>>>>>>>>>>>> > >>>>>>>>>>>>> Jiangjie (Becket) Qin > >>>>>>>>>>>>> > >>>>>>>>>>>>> > >>>>>>>>>>>>> On Wed, Oct 25, 2023 at 11:55 PM Jiabao Sun > >>>>>>>>>>>>> <jiabao....@xtransfer.cn.invalid> wrote: > >>>>>>>>>>>>> > >>>>>>>>>>>>>> Thanks Jane for the detailed explanation. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> I think that for users, we should respect conventions over > >>>>>>>>>>>>>> configurations. > >>>>>>>>>>>>>> Conventions can be default values explicitly specified in > >>>>>>>>>>>>>> configurations, or they can be behaviors that follow > previous > >>>>>>>>>> versions. > >>>>>>>>>>>>>> If the same code has different behaviors in different > versions, > >>>>> it > >>>>>>>>>> would > >>>>>>>>>>>>>> be a very bad thing. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> I agree that for regular users, it is not necessary to > >>> understand > >>>>>>>> all > >>>>>>>>>>>>>> the configurations related to Flink. > >>>>>>>>>>>>>> By following conventions, they can have a good experience. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Let's get back to the practical situation and consider it. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Case 1: > >>>>>>>>>>>>>> The user is not familiar with the purpose of the > >>>>>>>>>>>>>> table.optimizer.source.predicate-pushdown-enabled > configuration > >>>>> but > >>>>>>>>>> follows > >>>>>>>>>>>>>> the convention of allowing predicate pushdown to the source > by > >>>>>>>>>> default. > >>>>>>>>>>>>>> Just understanding the source.predicate-pushdown-enabled > >>>>>>>> configuration > >>>>>>>>>>>>>> and performing fine-grained toggle control will work well. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Case 2: > >>>>>>>>>>>>>> The user understands the meaning of the > >>>>>>>>>>>>>> table.optimizer.source.predicate-pushdown-enabled > configuration > >>>>> and > >>>>>>>>>> has set > >>>>>>>>>>>>>> its value to false. > >>>>>>>>>>>>>> We have reason to believe that the user understands the > meaning > >>>>> of > >>>>>>>> the > >>>>>>>>>>>>>> predicate pushdown configuration and the intention is to > >>> disable > >>>>>>>>>> predicate > >>>>>>>>>>>>>> pushdown (rather than whether or not to allow it). > >>>>>>>>>>>>>> The previous choice of globally disabling it is likely > because > >>> it > >>>>>>>>>>>>>> couldn't be disabled on individual sources. > >>>>>>>>>>>>>> From this perspective, if we provide more fine-grained > >>>>> configuration > >>>>>>>>>>>>>> support and provide detailed explanations of the > configuration > >>>>>>>>>> behaviors in > >>>>>>>>>>>>>> the documentation, > >>>>>>>>>>>>>> users can clearly understand the differences between these > two > >>>>>>>>>>>>>> configurations and use them correctly. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Also, I don't agree that > >>>>>>>>>>>>>> table.optimizer.source.predicate-pushdown-enabled = true and > >>>>>>>>>>>>>> source.predicate-pushdown-enabled = false means that the > local > >>>>>>>>>>>>>> configuration overrides the global configuration. > >>>>>>>>>>>>>> On the contrary, both configurations are functioning > correctly. > >>>>>>>>>>>>>> The optimizer allows predicate pushdown to all sources, but > >>> some > >>>>>>>>>> sources > >>>>>>>>>>>>>> can reject the filters pushed down by the optimizer. > >>>>>>>>>>>>>> This is natural, just like different components at different > >>>>> levels > >>>>>>>>>> are > >>>>>>>>>>>>>> responsible for different tasks. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> The more serious issue is that if > >>>>>>>> "source.predicate-pushdown-enabled" > >>>>>>>>>>>>>> does not respect > >>>>>>>> "table.optimizer.source.predicate-pushdown-enabled”, > >>>>>>>>>>>>>> the "table.optimizer.source.predicate-pushdown-enabled" > >>>>>>>> configuration > >>>>>>>>>>>>>> will be invalidated. > >>>>>>>>>>>>>> This means that regardless of whether > >>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" is set > to > >>>>> true > >>>>>>>> or > >>>>>>>>>>>>>> false, it will have no effect. > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>>>>>>> 2023年10月25日 22:24，Jane Chan <qingyue....@gmail.com> 写道： > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Hi Jiabao, > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Thanks for the in-depth clarification. Here are my cents > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> However, > "table.optimizer.source.predicate-pushdown-enabled" > >>> and > >>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" are configurations for > >>>>> different > >>>>>>>>>>>>>>>> components(optimizer and source operator). > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> We cannot assume that every user would be interested in > >>>>>>>> understanding > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>> internal components of Flink, such as the optimizer or > >>>>> connectors, > >>>>>>>>>> and > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>> specific configurations associated with each component. > >>> Instead, > >>>>>>>>>> users > >>>>>>>>>>>>>>> might be more concerned about knowing which configuration > >>>>> enables > >>>>>>>> or > >>>>>>>>>>>>>>> disables the filter push-down feature for all source > >>> connectors, > >>>>>>>> and > >>>>>>>>>>>>>> which > >>>>>>>>>>>>>>> parameter provides the flexibility to override this > behavior > >>>>> for a > >>>>>>>>>>>>>> single > >>>>>>>>>>>>>>> source if needed. > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> So, from this perspective, I am inclined to divide these > two > >>>>>>>>>> parameters > >>>>>>>>>>>>>>> based on the scope of their impact from the user's > perspective > >>>>>>>> (i.e. > >>>>>>>>>>>>>>> global-level or operator-level), rather than categorizing > them > >>>>>>>> based > >>>>>>>>>>>>>> on the > >>>>>>>>>>>>>>> component hierarchy from a developer's point of view. > >>> Therefore, > >>>>>>>>>> based > >>>>>>>>>>>>>> on > >>>>>>>>>>>>>>> this premise, it is intuitive and natural for users to > >>>>>>>>>>>>>>> understand fine-grained configuration options can override > >>>>> global > >>>>>>>>>>>>>>> configurations. > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Additionally, if "scan.filter-push-down.enabled" doesn't > >>>>> respect to > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" and > the > >>>>>>>> default > >>>>>>>>>>>>>> value > >>>>>>>>>>>>>>>> of "scan.filter-push-down.enabled" is defined as true, > >>>>>>>>>>>>>>>> it means that just modifying > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" as > false > >>>>> will > >>>>>>>>>>>>>> have no > >>>>>>>>>>>>>>>> effect, and filter pushdown will still be performed. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> If we define the default value of > >>>>> "scan.filter-push-down.enabled" > >>>>>>>> as > >>>>>>>>>>>>>>>> false, it would introduce a difference in behavior > compared > >>> to > >>>>> the > >>>>>>>>>>>>>> previous > >>>>>>>>>>>>>>>> version. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> <1>If I understand correctly, > "scan.filter-push-down.enabled" > >>>>> is a > >>>>>>>>>>>>>>> connector option, which means the only way to configure it > is > >>> to > >>>>>>>>>>>>>> explicitly > >>>>>>>>>>>>>>> specify it in DDL (no matter whether disable or enable), > and > >>> the > >>>>>>>> SET > >>>>>>>>>>>>>>> command is not applicable, so I think it's natural to still > >>>>> respect > >>>>>>>>>>>>>> user's > >>>>>>>>>>>>>>> specification here. Otherwise, users might be more confused > >>>>> about > >>>>>>>> why > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>> DDL does not work as expected, and the reason is just > because > >>>>> some > >>>>>>>>>>>>>> other > >>>>>>>>>>>>>>> "optimizer" configuration is set to a different value. > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> <2> From the implementation side, I am inclined to keep the > >>>>>>>>>> parameter's > >>>>>>>>>>>>>>> priority consistent for all conditions. > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Let "global" denote > >>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled", > >>>>>>>>>>>>>>> and let "per-source" denote "scan.filter-push-down.enabled" > >>> for > >>>>>>>>>>>>>> specific > >>>>>>>>>>>>>>> source T, the following Truth table (based on the current > >>>>> design) > >>>>>>>>>>>>>>> indicates the inconsistent behavior for "per-source > override > >>>>>>>> global". > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> .------------.---------------.------------------- > >>>>>>>>>>>>>>> ----.-------------------------------------. > >>>>>>>>>>>>>>> | global | per-source | push-down for T | per-source > >>> override > >>>>>>>>>> global > >>>>>>>>>>>>>> | > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>> > >>> > :-----------+--------------+-----------------------+------------------------------------: > >>>>>>>>>>>>>>> | true | false | false | Y > >>>>>>>>>>>>>>> | > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>> > >>> > :-----------+--------------+-----------------------+------------------------------------: > >>>>>>>>>>>>>>> | false | true | false | N > >>>>>>>>>>>>>>> | > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>> > >>> > .------------.---------------.-----------------------.-------------------------------------. > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>> Jane > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>> On Wed, Oct 25, 2023 at 6:22 PM Jiabao Sun < > >>>>>>>> jiabao....@xtransfer.cn > >>>>>>>>>>>>>> .invalid> > >>>>>>>>>>>>>>> wrote: > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> Thanks Benchao for the feedback. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> I understand that the configuration of global parallelism > and > >>>>> task > >>>>>>>>>>>>>>>> parallelism is at different granularities but with the > same > >>>>>>>>>>>>>> configuration. > >>>>>>>>>>>>>>>> However, > "table.optimizer.source.predicate-pushdown-enabled" > >>>>> and > >>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" are configurations for > >>>>> different > >>>>>>>>>>>>>>>> components(optimizer and source operator). > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> From a user's perspective, there are two scenarios: > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> 1. Disabling all filter pushdown > >>>>>>>>>>>>>>>> In this case, setting > >>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" > >>>>>>>>>>>>>>>> to false is sufficient to meet the requirement. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> 2. Disabling filter pushdown for specific sources > >>>>>>>>>>>>>>>> In this scenario, there is no need to adjust the value of > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled". > >>>>>>>>>>>>>>>> Instead, the focus should be on the configuration of > >>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" to meet the requirement. > >>>>>>>>>>>>>>>> In this case, users do not need to set > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" to > false > >>>>> and > >>>>>>>>>>>>>> manually > >>>>>>>>>>>>>>>> enable filter pushdown for specific sources. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> Additionally, if "scan.filter-push-down.enabled" doesn't > >>>>> respect > >>>>>>>> to > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" and > the > >>>>>>>> default > >>>>>>>>>>>>>> value > >>>>>>>>>>>>>>>> of "scan.filter-push-down.enabled" is defined as true, > >>>>>>>>>>>>>>>> it means that just modifying > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate-pushdown-enabled" as > false > >>>>> will > >>>>>>>>>>>>>> have no > >>>>>>>>>>>>>>>> effect, and filter pushdown will still be performed. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> If we define the default value of > >>>>> "scan.filter-push-down.enabled" > >>>>>>>> as > >>>>>>>>>>>>>>>> false, it would introduce a difference in behavior > compared > >>> to > >>>>> the > >>>>>>>>>>>>>> previous > >>>>>>>>>>>>>>>> version. > >>>>>>>>>>>>>>>> The same SQL query that could successfully push down > filters > >>> in > >>>>>>>> the > >>>>>>>>>>>>>> old > >>>>>>>>>>>>>>>> version but would no longer do so after the upgrade. > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> 2023年10月25日 17:10，Benchao Li <libenc...@apache.org> 写道： > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> Thanks Jiabao for the detailed explanations, that helps a > >>>>> lot, I > >>>>>>>>>>>>>>>>> understand your rationale now. > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> Correct me if I'm wrong. Your perspective is from > >>> "developer", > >>>>>>>>>> which > >>>>>>>>>>>>>>>>> means there is an optimizer and connector component, and > if > >>> we > >>>>>>>> want > >>>>>>>>>>>>>> to > >>>>>>>>>>>>>>>>> enable this feature (pushing filters down into > connectors), > >>>>> you > >>>>>>>>>> must > >>>>>>>>>>>>>>>>> enable it firstly in optimizer, and only then connector > has > >>>>> the > >>>>>>>>>>>>>> chance > >>>>>>>>>>>>>>>>> to decide to use it or not. > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> My perspective is from "user" that (Why a user should > care > >>>>> about > >>>>>>>>>> the > >>>>>>>>>>>>>>>>> difference of optimizer/connector) , this is a feature, > and > >>>>> has > >>>>>>>> two > >>>>>>>>>>>>>>>>> way to control it, one way is to config it job-level, the > >>>>> other > >>>>>>>> one > >>>>>>>>>>>>>> is > >>>>>>>>>>>>>>>>> in table properties. What a user expects is that they can > >>>>>>>> control a > >>>>>>>>>>>>>>>>> feature in a tiered way, that setting it per job, and > then > >>>>>>>>>>>>>>>>> fine-grained tune it per table. > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> This is some kind of similar to other concepts, such as > >>>>>>>>>> parallelism, > >>>>>>>>>>>>>>>>> users can set a job level default parallelism, and then > >>>>>>>>>> fine-grained > >>>>>>>>>>>>>>>>> tune it per operator. There may be more such debate in > the > >>>>> future > >>>>>>>>>>>>>>>>> e.g., we can have a job level config about adding key-by > >>>>> before > >>>>>>>>>>>>>> lookup > >>>>>>>>>>>>>>>>> join, and also a hint/table property way to fine-grained > >>>>> control > >>>>>>>> it > >>>>>>>>>>>>>>>>> per lookup operator. Hence we'd better find a unified way > >>> for > >>>>> all > >>>>>>>>>>>>>>>>> those similar kind of features. > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> Jiabao Sun <jiabao....@xtransfer.cn.invalid> > 于2023年10月25日周三 > >>>>>>>>>> 15:27写道： > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> Thanks Jane for further explanation. > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> These two configurations correspond to different levels. > >>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" does not make > >>>>>>>>>>>>>>>> "table.optimizer.source.predicate" invalid. > >>>>>>>>>>>>>>>>>> The planner will still push down predicates to all > sources. > >>>>>>>>>>>>>>>>>> Whether filter pushdown is allowed or not is determined > by > >>>>> the > >>>>>>>>>>>>>> specific > >>>>>>>>>>>>>>>> source's "scan.filter-push-down.enabled" configuration. > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> However, "table.optimizer.source.predicate" does > directly > >>>>> affect > >>>>>>>>>>>>>>>> "scan.filter-push-down.enabled”. > >>>>>>>>>>>>>>>>>> When the planner disables predicate pushdown, the > >>>>> source-level > >>>>>>>>>>>>>> filter > >>>>>>>>>>>>>>>> pushdown will also not be executed, even if the source > allows > >>>>>>>> filter > >>>>>>>>>>>>>>>> pushdown. > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> Whatever, in point 1 and 2, our expectation is > consistent. > >>>>>>>>>>>>>>>>>> For the 3rd point, I still think that the planner-level > >>>>>>>>>>>>>> configuration > >>>>>>>>>>>>>>>> takes precedence over the source-level configuration. > >>>>>>>>>>>>>>>>>> It may seem counterintuitive when we globally disable > >>>>> predicate > >>>>>>>>>>>>>>>> pushdown but allow filter pushdown at the source level. > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> 2023年10月25日 14:35，Jane Chan <qingyue....@gmail.com> > 写道： > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> Hi Jiabao, > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> Thanks for clarifying this. While by > >>>>>>>>>> "scan.filter-push-down.enabled > >>>>>>>>>>>>>>>> takes a > >>>>>>>>>>>>>>>>>>> higher priority" I meant that this value should be > >>> respected > >>>>>>>>>>>>>> whenever > >>>>>>>>>>>>>>>> it is > >>>>>>>>>>>>>>>>>>> set explicitly. > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> The conclusion that > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> 2. "table.optimizer.source.predicate" = "true" and > >>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" = "false" > >>>>>>>>>>>>>>>>>>>> Allow the planner to perform predicate pushdown, but > >>>>>>>> individual > >>>>>>>>>>>>>>>> sources do > >>>>>>>>>>>>>>>>>>>> not enable filter pushdown. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> This indicates that the option > >>>>> "scan.filter-push-down.enabled = > >>>>>>>>>>>>>> false" > >>>>>>>>>>>>>>>> for > >>>>>>>>>>>>>>>>>>> an individual source connector does indeed override the > >>>>>>>>>>>>>> global-level > >>>>>>>>>>>>>>>>>>> planner settings to make a difference. And thus "has a > >>>>> higher > >>>>>>>>>>>>>>>> priority". > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> While for > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> 3. "table.optimizer.source.predicate" = "false" > >>>>>>>>>>>>>>>>>>>> Predicate pushdown is not allowed for the planner. > >>>>>>>>>>>>>>>>>>>> Regardless of the value of the > >>>>> "scan.filter-push-down.enabled" > >>>>>>>>>>>>>>>>>>>> configuration, filter pushdown is disabled. > >>>>>>>>>>>>>>>>>>>> In this scenario, the behavior remains consistent with > >>> the > >>>>> old > >>>>>>>>>>>>>>>> version as > >>>>>>>>>>>>>>>>>>>> well. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> I still think "scan.filter-push-down.enabled" should > also > >>> be > >>>>>>>>>>>>>> respected > >>>>>>>>>>>>>>>> if > >>>>>>>>>>>>>>>>>>> it is enabled for individual connectors. WDYT? > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>> Jane > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>> On Wed, Oct 25, 2023 at 1:27 PM Jiabao Sun < > >>>>>>>>>>>>>> jiabao....@xtransfer.cn > >>>>>>>>>>>>>>>> .invalid> > >>>>>>>>>>>>>>>>>>> wrote: > >>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> Thanks Benchao for the feedback. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> For the current proposal, we recommend keeping the > >>> default > >>>>>>>> value > >>>>>>>>>>>>>> of > >>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" as true, > >>>>>>>>>>>>>>>>>>>> and setting the the default value of newly introduced > >>>>> option > >>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" to true as well. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> The main purpose of doing this is to maintain > consistency > >>>>> with > >>>>>>>>>>>>>>>> previous > >>>>>>>>>>>>>>>>>>>> versions, as whether to perform > >>>>>>>>>>>>>>>>>>>> filter pushdown in the old version solely depends on > the > >>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" option. > >>>>>>>>>>>>>>>>>>>> That means by default, as long as a TableSource > >>> implements > >>>>> the > >>>>>>>>>>>>>>>>>>>> SupportsFilterPushDown interface, filter pushdown is > >>>>> allowed. > >>>>>>>>>>>>>>>>>>>> And it seems that we don't have much benefit in > changing > >>>>> the > >>>>>>>>>>>>>> default > >>>>>>>>>>>>>>>> value > >>>>>>>>>>>>>>>>>>>> of "table.optimizer.source.predicate" to false. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> Regarding the priority of these two configurations, I > >>>>> believe > >>>>>>>>>> that > >>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" > >>>>>>>>>>>>>>>>>>>> takes precedence over "scan.filter-push-down.enabled" > and > >>>>> it > >>>>>>>>>>>>>> exhibits > >>>>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>> following behavior. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> 1. "table.optimizer.source.predicate" = "true" and > >>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" = "true" > >>>>>>>>>>>>>>>>>>>> This is the default behavior, allowing filter pushdown > >>> for > >>>>>>>>>>>>>> sources. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> 2. "table.optimizer.source.predicate" = "true" and > >>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" = "false" > >>>>>>>>>>>>>>>>>>>> Allow the planner to perform predicate pushdown, but > >>>>>>>> individual > >>>>>>>>>>>>>>>> sources do > >>>>>>>>>>>>>>>>>>>> not enable filter pushdown. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> 3. "table.optimizer.source.predicate" = "false" > >>>>>>>>>>>>>>>>>>>> Predicate pushdown is not allowed for the planner. > >>>>>>>>>>>>>>>>>>>> Regardless of the value of the > >>>>> "scan.filter-push-down.enabled" > >>>>>>>>>>>>>>>>>>>> configuration, filter pushdown is disabled. > >>>>>>>>>>>>>>>>>>>> In this scenario, the behavior remains consistent with > >>> the > >>>>> old > >>>>>>>>>>>>>>>> version as > >>>>>>>>>>>>>>>>>>>> well. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> From an implementation perspective, setting the > priority > >>> of > >>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" higher than > >>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" is difficult to > >>> achieve > >>>>>>>> now. > >>>>>>>>>>>>>>>>>>>> Because the PushFilterIntoSourceScanRuleBase at the > >>> planner > >>>>>>>>>> level > >>>>>>>>>>>>>>>> takes > >>>>>>>>>>>>>>>>>>>> precedence over the source-level FilterPushDownSpec. > >>>>>>>>>>>>>>>>>>>> Only when the PushFilterIntoSourceScanRuleBase is > >>> enabled, > >>>>>>>> will > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>> Source-level filter pushdown be performed. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> Additionally, in my opinion, there doesn't seem to be > >>> much > >>>>>>>>>>>>>> benefit in > >>>>>>>>>>>>>>>>>>>> setting a higher priority for > >>>>> "scan.filter-push-down.enabled". > >>>>>>>>>>>>>>>>>>>> It may instead affect compatibility and increase > >>>>>>>> implementation > >>>>>>>>>>>>>>>> complexity. > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> WDYT? > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> 2023年10月25日 11:56，Benchao Li <libenc...@apache.org> > 写道： > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> I agree with Jane that fine-grained configurations > >>> should > >>>>>>>> have > >>>>>>>>>>>>>> higher > >>>>>>>>>>>>>>>>>>>>> priority than job level configurations. > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> For current proposal, we can achieve that: > >>>>>>>>>>>>>>>>>>>>> - Set "table.optimizer.source.predicate" = "true" to > >>>>> enable > >>>>>>>> by > >>>>>>>>>>>>>>>>>>>>> default, and set ""scan.filter-push-down.enabled" = > >>>>> "false" > >>>>>>>> to > >>>>>>>>>>>>>>>> disable > >>>>>>>>>>>>>>>>>>>>> it per table source > >>>>>>>>>>>>>>>>>>>>> - Set "table.optimizer.source.predicate" = "false" to > >>>>> disable > >>>>>>>>>> by > >>>>>>>>>>>>>>>>>>>>> default, and set ""scan.filter-push-down.enabled" = > >>>>> "true" to > >>>>>>>>>>>>>> enable > >>>>>>>>>>>>>>>>>>>>> it per table source > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> Jane Chan <qingyue....@gmail.com> 于2023年10月24日周二 > >>> 23:55写道： > >>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> I believe that the configuration > >>>>>>>>>>>>>> "table.optimizer.source.predicate" > >>>>>>>>>>>>>>>>>>>> has a > >>>>>>>>>>>>>>>>>>>>>>> higher priority at the planner level than the > >>>>> configuration > >>>>>>>>>> at > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>> source > >>>>>>>>>>>>>>>>>>>>>>> level, > >>>>>>>>>>>>>>>>>>>>>>> and it seems easy to implement now. > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>> Correct me if I'm wrong, but I think the > fine-grained > >>>>>>>>>>>>>> configuration > >>>>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" should have a higher > >>>>>>>> priority > >>>>>>>>>>>>>>>> because > >>>>>>>>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>>>> default value of "table.optimizer.source.predicate" > is > >>>>> true. > >>>>>>>>>> As > >>>>>>>>>>>>>> a > >>>>>>>>>>>>>>>>>>>> result, > >>>>>>>>>>>>>>>>>>>>>> turning off filter push-down for a specific source > will > >>>>> not > >>>>>>>>>> take > >>>>>>>>>>>>>>>> effect > >>>>>>>>>>>>>>>>>>>>>> unless the default value of > >>>>>>>> "table.optimizer.source.predicate" > >>>>>>>>>>>>>> is > >>>>>>>>>>>>>>>>>>>> changed > >>>>>>>>>>>>>>>>>>>>>> to false, or, alternatively, let users manually set > >>>>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" to false first > and > >>>>> then > >>>>>>>>>>>>>>>> selectively > >>>>>>>>>>>>>>>>>>>>>> enable filter push-down for the desired sources, > which > >>> is > >>>>>>>> less > >>>>>>>>>>>>>>>>>>>> intuitive. > >>>>>>>>>>>>>>>>>>>>>> WDYT? > >>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>> Jane > >>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>> On Tue, Oct 24, 2023 at 6:05 PM Jiabao Sun < > >>>>>>>>>>>>>> jiabao....@xtransfer.cn > >>>>>>>>>>>>>>>>>>>> .invalid> > >>>>>>>>>>>>>>>>>>>>>> wrote: > >>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> Thanks Jane, > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> I believe that the configuration > >>>>>>>>>>>>>> "table.optimizer.source.predicate" > >>>>>>>>>>>>>>>>>>>> has a > >>>>>>>>>>>>>>>>>>>>>>> higher priority at the planner level than the > >>>>> configuration > >>>>>>>>>> at > >>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>> source > >>>>>>>>>>>>>>>>>>>>>>> level, > >>>>>>>>>>>>>>>>>>>>>>> and it seems easy to implement now. > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>> 2023年10月24日 17:36，Jane Chan < > qingyue....@gmail.com> > >>>>> 写道： > >>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>> Hi Jiabao, > >>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>> Thanks for driving this discussion. I have a small > >>>>>>>> question > >>>>>>>>>>>>>> that > >>>>>>>>>>>>>>>> will > >>>>>>>>>>>>>>>>>>>>>>>> "scan.filter-push-down.enabled" take precedence > over > >>>>>>>>>>>>>>>>>>>>>>>> "table.optimizer.source.predicate" when the two > >>>>> parameters > >>>>>>>>>>>>>> might > >>>>>>>>>>>>>>>>>>>> conflict > >>>>>>>>>>>>>>>>>>>>>>>> each other? > >>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>>> Jane > >>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>> On Tue, Oct 24, 2023 at 5:05 PM Jiabao Sun < > >>>>>>>>>>>>>>>> jiabao....@xtransfer.cn > >>>>>>>>>>>>>>>>>>>>>>> .invalid> > >>>>>>>>>>>>>>>>>>>>>>>> wrote: > >>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> Thanks Jark, > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> If we only add configuration without adding the > >>>>>>>>>>>>>>>> enableFilterPushDown > >>>>>>>>>>>>>>>>>>>>>>>>> method in the SupportsFilterPushDown interface, > >>>>>>>>>>>>>>>>>>>>>>>>> each connector would have to handle the same > logic > >>> in > >>>>> the > >>>>>>>>>>>>>>>>>>>> applyFilters > >>>>>>>>>>>>>>>>>>>>>>>>> method to determine whether filter pushdown is > >>> needed. > >>>>>>>>>>>>>>>>>>>>>>>>> This would increase complexity and violate the > >>>>> original > >>>>>>>>>>>>>> behavior > >>>>>>>>>>>>>>>> of > >>>>>>>>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>>>>>>> applyFilters method. > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> On the contrary, we only need to pass the > >>>>> configuration > >>>>>>>>>>>>>>>> parameter in > >>>>>>>>>>>>>>>>>>>> the > >>>>>>>>>>>>>>>>>>>>>>>>> newly added enableFilterPushDown method > >>>>>>>>>>>>>>>>>>>>>>>>> to decide whether to perform predicate pushdown. > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> I think this approach would be clearer and > simpler. > >>>>>>>>>>>>>>>>>>>>>>>>> WDYT? > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> 2023年10月24日 16:58，Jark Wu <imj...@gmail.com> > 写道： > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> Hi JIabao, > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> I think the current interface can already > satisfy > >>>>> your > >>>>>>>>>>>>>>>> requirements. > >>>>>>>>>>>>>>>>>>>>>>>>>> The connector can reject all the filters by > >>> returning > >>>>>>>> the > >>>>>>>>>>>>>> input > >>>>>>>>>>>>>>>>>>>> filters > >>>>>>>>>>>>>>>>>>>>>>>>>> as `Result#remainingFilters`. > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> So maybe we don't need to introduce a new > method to > >>>>>>>>>> disable > >>>>>>>>>>>>>>>>>>>>>>>>>> pushdown, but just introduce an option for the > >>>>> specific > >>>>>>>>>>>>>>>> connector. > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>>>>> Jark > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>> On Tue, 24 Oct 2023 at 16:38, Leonard Xu < > >>>>>>>>>> xbjt...@gmail.com > >>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> wrote: > >>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>> Thanks @Jiabao for kicking off this discussion. > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>> Could you add a section to explain the > difference > >>>>>>>> between > >>>>>>>>>>>>>>>> proposed > >>>>>>>>>>>>>>>>>>>>>>>>>>> connector level config > >>>>> `scan.filter-push-down.enabled` > >>>>>>>>>> and > >>>>>>>>>>>>>>>> existing > >>>>>>>>>>>>>>>>>>>>>>>>> query > >>>>>>>>>>>>>>>>>>>>>>>>>>> level config > >>>>>>>>>>>>>>>> `table.optimizer.source.predicate-pushdown-enabled` ? > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>>>>>> Leonard > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> 2023年10月24日 下午4:18，Jiabao Sun < > >>>>>>>> jiabao....@xtransfer.cn > >>>>>>>>>>>>>>>> .INVALID> > >>>>>>>>>>>>>>>>>>>> 写道： > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Hi Devs, > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> I would like to start a discussion on > FLIP-377: > >>>>>>>> support > >>>>>>>>>>>>>>>>>>>> configuration > >>>>>>>>>>>>>>>>>>>>>>>>> to > >>>>>>>>>>>>>>>>>>>>>>>>>>> disable filter pushdown for Table/SQL > Sources[1]. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Currently, Flink Table/SQL does not expose > >>>>>>>> fine-grained > >>>>>>>>>>>>>>>> control > >>>>>>>>>>>>>>>>>>>> for > >>>>>>>>>>>>>>>>>>>>>>>>>>> users to enable or disable filter pushdown. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> However, filter pushdown has some side > effects, > >>>>> such > >>>>>>>> as > >>>>>>>>>>>>>>>> additional > >>>>>>>>>>>>>>>>>>>>>>>>>>> computational pressure on external systems. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Moreover, Improper queries can lead to issues > >>> such > >>>>> as > >>>>>>>>>> full > >>>>>>>>>>>>>>>> table > >>>>>>>>>>>>>>>>>>>>>>> scans, > >>>>>>>>>>>>>>>>>>>>>>>>>>> which in turn can impact the stability of > external > >>>>>>>>>> systems. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Suppose we have an SQL query with two sources: > >>>>> Kafka > >>>>>>>>>> and a > >>>>>>>>>>>>>>>>>>>> database. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> The database is sensitive to pressure, and we > >>> want > >>>>> to > >>>>>>>>>>>>>>>> configure > >>>>>>>>>>>>>>>>>>>> it to > >>>>>>>>>>>>>>>>>>>>>>>>>>> not perform filter pushdown to the database > >>> source. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> However, we still want to perform filter > pushdown > >>>>> to > >>>>>>>> the > >>>>>>>>>>>>>> Kafka > >>>>>>>>>>>>>>>>>>>> source > >>>>>>>>>>>>>>>>>>>>>>>>> to > >>>>>>>>>>>>>>>>>>>>>>>>>>> decrease network IO. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> I propose to support configuration to disable > >>>>> filter > >>>>>>>>>> push > >>>>>>>>>>>>>>>> down for > >>>>>>>>>>>>>>>>>>>>>>>>>>> Table/SQL sources to let user decide whether to > >>>>> perform > >>>>>>>>>>>>>> filter > >>>>>>>>>>>>>>>>>>>>>>> pushdown. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Looking forward to your feedback. > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> [1] > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>> > >>> > https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=276105768 > >>>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>>>>>>>>> Jiabao > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> -- > >>>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>>>>>> Benchao Li > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> -- > >>>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>>> Best, > >>>>>>>>>>>>>>>>> Benchao Li > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>>>>>> > >>>>>>>>>> > >>>>>>>>>> > >>>>>>>> > >>>>>>>> > >>>>>> > >>>>> > >>>>> > >>>>> > >>> > >>> > >>> > > > >
