Is there any overlap with the file adapter? The file adapter can read using various transports (file, http, optional compression) and various formats (csv, json, html tables).
> On May 31, 2022, at 12:47 PM, Gavin Ray <ray.gavi...@gmail.com> wrote: > > I don't think it's SQL Standard, but essentially it takes a text value > containing JSON data (one record or an array) and converts it into a > relational table: > > https://docs.oracle.com/database/121/SQLRF/functions092.htm > > I've managed to get most of this working, now I seem to be failing to put > the syntax together correctly for the query > I currently have: > - A UDF ("HTTP_GET") which can make HTTP calls and return the data as a > String > - A table type for Collection<Map<String, Object>> ("MapCollectionTable") > - A TableFunctionImpl ("JsonTableFunction"), which takes a JSON string, > reads it with Jackson, and converts it into a "MapCollectionTable" > > The following work: > > SELECT HTTP_GET('https://jsonplaceholder.typicode.com/posts') > > SELECT * FROM TABLE( > JSON_TABLE('[{ "id": "1", "name": "foo" }, { "id": "2", "name": "bar" > }]')) > > But trying to combine them fails =/ > > SELECT * FROM TABLE( > JSON_TABLE(HTTP_GET('https://jsonplaceholder.typicode.com/posts'))) > > The TableFunctionImpl is receiving "null" for the JSON value > I guess it's maybe expecting static data? > > Calcite JSON_TABLE wip 2 (github.com) > <https://gist.github.com/GavinRay97/fbd16dd2b893cb59c720e6d514c5e39a#file-main-java> > > On Tue, May 31, 2022 at 2:44 PM Julian Hyde <jh...@apache.org> wrote: > >> What is JSON_TABLE? Is it in the SQL standard? Can you give a simple >> example? >> >> On Tue, May 31, 2022 at 10:03 AM Gavin Ray <ray.gavi...@gmail.com> wrote: >>> >>> I dug up some examples from Github of using the "TableFunctionImpl" >> class: >>> >>> mat-calcite-plugin/TableFunctions.java at >>> a57a5ba80768066714c22bd9e8a9b529d4cb9a6b · vlsi/mat-calcite-plugin >>> (github.com) >>> < >> https://github.com/vlsi/mat-calcite-plugin/blob/a57a5ba80768066714c22bd9e8a9b529d4cb9a6b/MatCalcitePlugin/src/com/github/vlsi/mat/calcite/functions/TableFunctions.java >>> >>> Calcite_sql_driver/MazeTable.java at >>> 6819088123e67631367ca927b112b58e4eb90829 · dream001/Calcite_sql_driver >>> (github.com) >>> < >> https://github.com/dream001/Calcite_sql_driver/blob/6819088123e67631367ca927b112b58e4eb90829/src/test/java/com/yonyou/calcite/MazeTable.java >>> >>> >>> Currently trying to get a TableFunction that just returns a Map<String, >>> Object> as a relation to work >>> Have the below -- calling this shows that the function IS invoked, but >> the >>> data it gives back is garbage: >>> >>> Calcite JSON_TABLE WIP (github.com) >>> <https://gist.github.com/GavinRay97/b42c69992a0d0c3a01f1c7e1b9ab1999> >>> >>> This is the output of main() >>> >>> json = {"id":1, "name":"John"} >>> json = {"id":1, "name":"John"} >>> json = {"id":1, "name":"John"} >>> EXPR$0: id >>> EXPR$0: id >>> >>> I'm doing something wrong here for sure, lol. >>> >>> >>> On Tue, May 31, 2022 at 11:35 AM Gavin Ray <ray.gavi...@gmail.com> >> wrote: >>> >>>> I'm interested in implementing JSON_TABLE functionality for Calcite >>>> >>>> This opens up some neat usecases, like adding HTTP request UDF's >>>> then using JSON_TABLE to convert the result into a table: >>>> >>>> SELECT JSON_TABLE( >>>> HTTP_GET('http://localhost:8080/api/v1/users/1')) >>>> >>>> Adding support for all of the functionality seems difficult, >>>> but I'm wondering whether this could be done as a "SqlTableFunction" >> UDF? >>>> >>>> I'm thinking it might be possible if the JSON_TABLE udf >>>> expects Map<String, Object> and does inference based on that? >>>> >>>> Something like: >>>> >>>> WITH users AS ( >>>> SELECT HTTP_GET('http://localhost:8080/api/v1/users') >>>> ) SELECT >>>> id, >>>> name >>>> FROM >>>> JSON_TABLE(JSON_PATH(users, "$.0")) >>>> >>>> Does anyone have ideas or see issues with this approach? >>>> Thank you =) >>>> >>>> >>>> >>>> >>
