hi statmatis: It's also possible that we could do better in both ways, as Hongze Zhang said. One of the initial reasons I implemented json_type was to use it in flink as well. However, we know that flink is not open to support a dialect like mysql. best qianjin
------------------ 原始邮件 ------------------ 发件人: "Hongze Zhang"<notify...@126.com>; 发送时间: 2019年2月1日(星期五) 中午1:09 收件人: "dev@calcite.apache.org"<dev@calcite.apache.org>; 主题: Re: Re: Integrating MySQL's JSON functions Hi Stamatis, Thanks for mentioning MySQLOperatorTable! I just read some code about the usage of OracleOperatorTable in Calcite, but I am now not strongly inclined to add MySQL's JSON functions to MySQLOperatorTable. MySQL's JSON functions are rarely conflict with what are from standard, and they extends the JSON ability of MySQL in many sides. I think it might be a good try to treat functions from both MySQL's and standard's as a whole JSON operator suite. Users may want to directly use any function they know, I think it is better to not to confuse them with the truth that what's in standard and what's not. For the conflict part like JSON_OBJECT(key , value) and JSON_OBJECT(key : value), I think we can just support both. What do you think? Hongze From: Stamatis Zampetakis Date: 2019-02-01 06:32 To: dev Subject: Re: Integrating MySQL's JSON functions Nice document Hongze! Since the functions are only present in MySQL why not create a MySQLOperatorTable and put them there? I went over the discussion in CALCITE-2791 but I did not understand why it is preferable to put them in the SqlStdOperatorTable. Στις Πέμ, 31 Ιαν 2019 στις 10:51 μ.μ., ο/η Julian Hyde <jh...@apache.org> έγραψε: > +1 > > In the reference doc, let’s make it clear that these are in MySQL but not > in the standard. (Unlike some of their other extensions to standard SQL, > MySQL seem to have done a good job - they are well-designed and > well-documented.) > > > On Jan 31, 2019, at 10:20 AM, Hongze Zhang <notify...@126.com> wrote: > > > > Hi all, > > > > > > There is a PR CALCITE-2791[1] from xuqianjin about adding a MySQL > function JSON_TYPE[2], and I want to know what do you think about it. > > > > > > JSON_TYPE is not a standard JSON function defined by SQL:2016. In MySQL > the use of this function is to get the type of a JSON doc. The similar > operator in Calcite 1.18.0 is "IS JSON (VALUE/SCALAR/OBJECT/ARRAY)", > however sometimes JSON_TYPE can do more than it. > > > > As for other non-standard JSON functions, I made a simple summary table > about JSON support (mainly as functions) details of some of most important > SQL implementations. you can open it via link > https://docs.google.com/spreadsheets/d/1A6vrEEu3WK49dJ5mfaYeMLFvAy0JR9uoJsiaKhxUal4/edit#gid=0 > > > > > > And I suggest to introduce some JSON functions that is from MySQL and > might be useful for Calcite but not supported, not Just JSON_TYPE: > > 1. JSON_INSERT / JSON_SET / JSON_REPLACE /JSON_REMOVE [3] > > 2. JSON_DEPTH / JSON_LENGTH / JSON_TYPE [4] > > I think the PR[1] can be a good start. > > > > > > Does anyone have thought about this? Looking forward to your reply. > > > > > > [1] https://issues.apache.org/jira/browse/CALCITE-2791 > > [2] > https://dev.mysql.com/doc/refman/8.0/en/json-attribute-functions.html#function_json-type > > [3] > https://dev.mysql.com/doc/refman/8.0/en/json-modification-functions.html > > [4] > https://dev.mysql.com/doc/refman/8.0/en/json-attribute-functions.html > >
