Re: remaining sql/json patches

On Mon, Jan 22, 2024 at 11:46 PM jian he <jian.universality@gmail.com> wrote:
>
> On Mon, Jan 22, 2024 at 10:28 PM Amit Langote <amitlangote09@gmail.com> wrote:
> >
> > > based on v35.
> > > Now I only applied from 0001 to 0007.
> > > For {DEFAULT expression  ON EMPTY}  | {DEFAULT expression ON ERROR}
> > > restrict DEFAULT expression be either Const node or FuncExpr node.
> > > so these 3 SQL/JSON functions can be used in the btree expression index.
> >
> > I'm not really excited about adding these restrictions into the
> > transformJsonFuncExpr() path.  Index or any other code that wants to
> > put restrictions already have those in place, no need to add them
> > here.  Moreover, by adding these restrictions, we might end up
> > preventing users from doing useful things with this like specify
> > column references.  If there are semantic issues with allowing that,
> > we should discuss them.
> >
>
> after applying v36.
> The following index creation and query operation works. I am not 100%
> sure about these cases.
> just want confirmation, sorry for bothering you....
>
> drop table t;
> create table t(a jsonb, b  int);
> insert into t select '{"hello":11}',1;
> insert into t select '{"hello":12}',2;
> CREATE INDEX t_idx2 ON t (JSON_query(a, '$.hello1' RETURNING int
> default b + random() on error));
> CREATE INDEX t_idx3 ON t (JSON_query(a, '$.hello1' RETURNING int
> default random()::int on error));
> SELECT JSON_query(a, '$.hello1'  RETURNING int default ret_setint() on
> error) from t;

I forgot to attach ret_setint defition.

create or replace function ret_setint() returns setof integer as
$$
begin
    -- perform pg_sleep(0.1);
    return query execute 'select 1 union all select 1';
end;
$$
language plpgsql IMMUTABLE;

-----------------------------------------
In the function transformJsonExprCommon, we have
`JsonExpr   *jsexpr = makeNode(JsonExpr);`
then the following 2 assignments are not necessary.

/* Both set in the caller. */
jsexpr->result_coercion = NULL;
jsexpr->omit_quotes = false;

So I removed it.

JSON_VALUE OMIT QUOTES by default, so I set it accordingly.
I also changed coerceJsonFuncExprOutput accordingly