Thanks to Peter for the proposal! I left some comments in the google doc. Besides what Bowen pointed out, I'm unclear about how things work end to end from the document. For instance, SQL DDL-like function definition is mentioned. I guess just having a DDL for it doesn't explain how it's supported functionally. I think it's better to have some clarification on what is expected work and what's for the future.
Thanks, Xuefu On Tue, Oct 15, 2019 at 11:05 AM Bowen Li <bowenl...@gmail.com> wrote: > Hi Zhenqiu, > > Thanks for taking on this effort! > > A couple questions: > - Though this FLIP is about function DDL, can we also think about how the > created functions can be mapped to CatalogFunction and see if we need to > modify CatalogFunction interface? Syntax changes need to be backed by the > backend. > - Can we define a clearer, smaller scope targeting for Flink 1.10 among all > the proposed changes? The current overall scope seems to be quite wide, and > it may be unrealistic to get everything in a single release, or even a > couple. However, I believe the most common user story can be something as > simple as "being able to create and persist a java class-based udf and use > it later in queries", which will add great value for most Flink users and > is achievable in 1.10. > > Bowen > > On Sun, Oct 13, 2019 at 10:46 PM Peter Huang <huangzhenqiu0...@gmail.com> > wrote: > > > Dear Community, > > > > FLIP-79 Flink Function DDL Support > > < > > > https://docs.google.com/document/d/16kkHlis80s61ifnIahCj-0IEdy5NJ1z-vGEJd_JuLog/edit# > > > > > > > This proposal aims to support function DDL with the consideration of SQL > > syntax, language compliance, and advanced external UDF lib registration. > > The Flink DDL is initialized and discussed in the design > > < > > > https://docs.google.com/document/d/1TTP-GCC8wSsibJaSUyFZ_5NBAHYEB1FVmPpP7RgDGBA/edit#heading=h.wpsqidkaaoil > > > > > [1] by Shuyi Chen and Timo. As the initial discussion mainly focused on > the > > table, type and view. FLIP-69 [2] extend it with a more detailed > discussion > > of DDL for catalog, database, and function. Original the function DDL was > > under the scope of FLIP-69. After some discussion > > <https://issues.apache.org/jira/browse/FLINK-7151> with the community, > we > > found that there are several ongoing efforts, such as FLIP-64 [3], > FLIP-65 > > [4], and FLIP-78 [5]. As they will directly impact the SQL syntax of > > function DDL, the proposal wants to describe the problem clearly with the > > consideration of existing works and make sure the design aligns with > > efforts of API change of temporary objects and type inference for UDF > > defined by different languages. > > > > The FlLIP outlines the requirements from related works, and propose a SQL > > syntax to meet those requirements. The corresponding implementation is > also > > discussed. Please kindly review and give feedback. > > > > > > Best Regards > > Peter Huang > > > -- Xuefu Zhang "In Honey We Trust!"