Horton

Re: remaining sql/json patches

jian he <jian.universality@gmail.com>

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From: jian he <jian.universality@gmail.com>
To: Amit Langote <amitlangote09@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: 2024-04-04T07:50:02Z
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 Thu, Apr 4, 2024 at 2:41 PM jian he <jian.universality@gmail.com> wrote:
>
> On Wed, Apr 3, 2024 at 8:39 PM Amit Langote <amitlangote09@gmail.com> wrote:
> >
> > Attached updated patches.  I have addressed your doc comments on 0001,
> > but not 0002 yet.
> >
>
about v49, 0002.

--tests setup.
drop table if exists s cascade;
create table s(js jsonb);
insert into s values
('{"a":{"za":[{"z1": [11,2222]},{"z21": [22, 234,2345]},{"z22": [32,
204,145]}]},"c": 3}'),
('{"a":{"za":[{"z1": [21,4222]},{"z21": [32, 134,1345]}]},"c": 10}');

after playing around, I found, the non-nested column will be sorted first,
and the nested column will be ordered as is.
the below query, column "xx1" will be the first column, "xx" will be
the second column.

SELECT sub.* FROM s,(values(23)) x(x),generate_series(13, 13) y,
JSON_TABLE(js, '$' as c1 PASSING x AS x, y AS y COLUMNS(
NESTED PATH '$.a.za[2]' as n3 columns (NESTED PATH '$.z22[*]' as z22
COLUMNS (c int path  '$')),
NESTED PATH '$.a.za[1]' as n4 columns (d int[] PATH '$.z21'),
NESTED PATH '$.a.za[0]' as n1 columns (NESTED PATH '$.z1[*]' as z1
COLUMNS (a int path  '$')),
xx1 int path '$.c',
NESTED PATH '$.a.za[1]' as n2 columns (NESTED PATH '$.z21[*]' as z21
COLUMNS (b int path '$')),
xx int path '$.c'
))sub;
maybe this behavior is fine. but there is no explanation?
--------------------------------------------------------------------------------
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -1327,6 +1327,7 @@ JsonPathMutableContext
 JsonPathParseItem
 JsonPathParseResult
 JsonPathPredicateCallback
+JsonPathSpec
this change is no need.

--------------------------------------------------------------------------------
+ if (scan->child)
+ get_json_table_nested_columns(tf, scan->child, context, showimplicit,
+  scan->colMax >= scan->colMin);
except parse_jsontable.c, we only use colMin, colMax in get_json_table_columns.
aslo in parse_jsontable.c, we do it via:

+ /* Start of column range */
+ colMin = list_length(tf->colvalexprs);
....
+ /* End of column range */
+ colMax = list_length(tf->colvalexprs) - 1;

maybe we can use (bool *) to tag whether this JsonTableColumn is nested or not
in transformJsonTableColumns.

currently colMin, colMax seems to make parsing back json_table (nested
path only) not working.
--------------------------------------------------------------------------------
I also added some slightly complicated tests to prove that the PASSING
clause works
with every level, aslo the multi level nesting clause works as intended.

As mentioned in the previous mail, parsing back nest columns
json_table expression
not working as we expected.

so the last view (jsonb_table_view7) I added,  the view definition is WRONG!!
the good news is the output is what we expected, the coverage is pretty high.