Horton

Re: remaining sql/json patches

amit <amitlangote09@gmail.com>

View thread
From: Amit Langote <amitlangote09@gmail.com>
To: jian he <jian.universality@gmail.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Himanshu Upadhyaya <upadhyaya.himanshu@gmail.com>, Erik Rijkers <er@xs4all.nl>, Andres Freund <andres@anarazel.de>, Andrew Dunstan <andrew@dunslane.net>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2024-04-03T12:38:59Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. SQL/JSON: Various improvements to SQL/JSON query function docs

  2. SQL/JSON: Fix some obsolete comments.

  3. SQL/JSON: Fix issues with DEFAULT .. ON ERROR / EMPTY

  4. JSON_TABLE: Add support for NESTED paths and columns

  5. Fix JsonExpr deparsing to emit QUOTES and WRAPPER correctly

  6. Fix typo introduced in 6185c9737

  7. Add basic JSON_TABLE() functionality

  8. Avoid splitting errmsg string to span multiple lines

  9. Add SQL/JSON query functions

  10. Implement various jsonpath methods

  11. Add soft error handling to some expression nodes

  12. Adjust populate_record_field() to handle errors softly

  13. Refactor code used by jsonpath executor to fetch variables

  14. Test EXPLAIN (FORMAT JSON) ... XMLTABLE

  15. Simplify productions for FORMAT JSON [ ENCODING name ]

  16. Add trailing commas to enum definitions

  17. doc: add missing <returnvalue> and whitespace

  18. Add more SQL/JSON constructor functions

  19. Rename a nonterminal used in SQL/JSON grammar

  20. Some refactoring to export json(b) conversion functions

  21. Don't include CaseTestExpr in JsonValueExpr.formatted_expr

  22. Code review for commit b6e1157e7d

  23. Pass constructName to transformJsonValueExpr()

  24. Unify JSON categorize type API and export for external use

  25. Make some indentation in gram.y consistent

  26. Allow most keywords to be used as column labels without requiring AS.

  27. Reduce size of backend scanner's tables.

  28. Use perfect hashing, instead of binary search, for keyword lookup.

Attachments

On Wed, Apr 3, 2024 at 4:16 PM jian he <jian.universality@gmail.com> wrote:
> On Wed, Apr 3, 2024 at 11:30 AM jian he <jian.universality@gmail.com> wrote:
> >
> > On Tue, Apr 2, 2024 at 9:57 PM Amit Langote <amitlangote09@gmail.com> wrote:
> > >
> > > Please let me know if you have further comments on 0001.  I'd like to
> > > get that in before spending more energy on 0002.
> > >
>
> -- a/src/backend/parser/parse_target.c
> +++ b/src/backend/parser/parse_target.c
> @@ -2019,6 +2019,9 @@ FigureColnameInternal(Node *node, char **name)
>   case JSON_VALUE_OP:
>   *name = "json_value";
>   return 2;
> + case JSON_TABLE_OP:
> + *name = "json_table";
> + return 2;
>   default:
>   elog(ERROR, "unrecognized JsonExpr op: %d",
>   (int) ((JsonFuncExpr *) node)->op);
>
> "case JSON_TABLE_OP part", no need?
> json_table output must provide column name and type?

That seems to be the case, so removed.

> I did some minor refactor transformJsonTableColumns, make the comments
> align with the function intention.

Thanks, but that seems a bit verbose.  I've reduced it down to what
gives enough information.

> in v48-0001, in transformJsonTableColumns we can `Assert(rawc->name);`.
> since non-nested JsonTableColumn must specify column name.
> in v48-0002, we can change to `if (rawc->coltype != JTC_NESTED)
> Assert(rawc->name);`

Ok, done.

> SELECT * FROM JSON_TABLE(jsonb '1', '$' COLUMNS (a int PATH '$.a' )
> ERROR ON ERROR) jt;
> ERROR:  no SQL/JSON item
>
> I thought it should just return NULL.
> In this case, I thought that
> (not column-level) ERROR ON ERROR should not interfere with "COLUMNS
> (a int PATH '$.a' )".

I think it does in another database's implementation, which must be
why the original authors decided that the table-level ERROR should
also be used for columns unless overridden.  But I agree that keeping
the two separate is better, so changed that way.

Attached updated patches.  I have addressed your doc comments on 0001,
but not 0002 yet.


>
> +-- Other miscellanous checks
> "miscellanous" should be "miscellaneous".
>
>
> overall the coverage is pretty high.
> the current test output looks fine.



--
Thanks, Amit Langote