Horton

Re: remaining sql/json patches

amit <amitlangote09@gmail.com>

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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: 2024-04-06T15:10:36Z
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.

Hi,

On Sat, Apr 6, 2024 at 3:55 PM jian he <jian.universality@gmail.com> wrote:
> On Sat, Apr 6, 2024 at 2:03 PM Amit Langote <amitlangote09@gmail.com> wrote:
> >
> > >
> > > * problem with type "char". the view def  output is not the same as
> > > the select * from v1.
> > >
> > > create or replace view v1 as
> > > SELECT col FROM s,
> > > JSON_TABLE(jsonb '{"d": ["hello", "hello1"]}', '$' as c1
> > > COLUMNS(col "char" path '$.d' without wrapper keep quotes))sub;
> > >
> > > \sv v1
> > > CREATE OR REPLACE VIEW public.v1 AS
> > >  SELECT sub.col
> > >    FROM s,
> > >     JSON_TABLE(
> > >             '{"d": ["hello", "hello1"]}'::jsonb, '$' AS c1
> > >             COLUMNS (
> > >                 col "char" PATH '$."d"'
> > >             )
> > >         ) sub
> > > one under the hood called JSON_QUERY_OP, another called JSON_VALUE_OP.
> >
> > Hmm, I don't see a problem as long as both are equivalent or produce
> > the same result.  Though, perhaps we could make
> > get_json_expr_options() also deparse JSW_NONE explicitly into "WITHOUT
> > WRAPPER" instead of a blank.  But that's existing code, so will take
> > care of it as part of the above open item.
> >
> > > I will do extensive checking for other types later, so far, other than
> > > these two issues,
> > > get_json_table_columns is pretty solid, I've tried nested columns with
> > > nested columns, it just works.
> >
> > Thanks for checking.
> >
> After applying v50, this type also has some issues.
> CREATE OR REPLACE VIEW t1 as
> SELECT sub.* FROM JSON_TABLE(jsonb '{"d": ["hello", "hello1"]}',
> '$' AS c1 COLUMNS (
> "tsvector0" tsvector path '$.d' without wrapper omit quotes,
> "tsvector1" tsvector path '$.d' without wrapper keep quotes))sub;
> table t1;
>
> return
>         tsvector0        |        tsvector1
> -------------------------+-------------------------
>  '"hello1"]' '["hello",' | '"hello1"]' '["hello",'
> (1 row)
>
> src5=# \sv t1
> CREATE OR REPLACE VIEW public.t1 AS
>  SELECT tsvector0,
>     tsvector1
>    FROM JSON_TABLE(
>             '{"d": ["hello", "hello1"]}'::jsonb, '$' AS c1
>             COLUMNS (
>                 tsvector0 tsvector PATH '$."d"' OMIT QUOTES,
>                 tsvector1 tsvector PATH '$."d"'
>             )
>         ) sub
>
> but
>
>  SELECT tsvector0,
>     tsvector1
>    FROM JSON_TABLE(
>             '{"d": ["hello", "hello1"]}'::jsonb, '$' AS c1
>             COLUMNS (
>                 tsvector0 tsvector PATH '$."d"' OMIT QUOTES,
>                 tsvector1 tsvector PATH '$."d"'
>             )
>         ) sub
>
> only return
>         tsvector0        | tsvector1
> -------------------------+-----------
>  '"hello1"]' '["hello",' |

Yep, we *should* fix get_json_expr_options() to emit KEEP QUOTES and
WITHOUT WRAPPER options so that transformJsonTableColumns() does the
correct thing when you execute the \sv output.  Like this:

diff --git a/src/backend/utils/adt/ruleutils.c
b/src/backend/utils/adt/ruleutils.c
index 283ca53cb5..5a6aabe100 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -8853,9 +8853,13 @@ get_json_expr_options(JsonExpr *jsexpr,
deparse_context *context,
             appendStringInfo(context->buf, " WITH CONDITIONAL WRAPPER");
         else if (jsexpr->wrapper == JSW_UNCONDITIONAL)
             appendStringInfo(context->buf, " WITH UNCONDITIONAL WRAPPER");
+        else if (jsexpr->wrapper == JSW_NONE)
+            appendStringInfo(context->buf, " WITHOUT WRAPPER");

         if (jsexpr->omit_quotes)
             appendStringInfo(context->buf, " OMIT QUOTES");
+        else
+            appendStringInfo(context->buf, " KEEP QUOTES");
     }

Will get that pushed tomorrow.  Thanks for the test case.

-- 
Thanks, Amit Langote