Re: SQL/JSON in PostgreSQL

On 15.09.2017 22:36, Oleg Bartunov wrote:

> On Fri, Sep 15, 2017 at 7:31 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Fri, Sep 15, 2017 at 10:10 AM, Daniel Gustafsson <daniel(at)yesql(dot)se> wrote:
>>> Can we expect a rebased version of this patch for this commitfest? Since it’s
>>> a rather large feature it would be good to get it in as early as we can in the
>>> process.
>> Again, given that this needs a "major" rebase and hasn't been updated
>> in a month, and given that the CF is already half over, this should
>> just be bumped to the next CF. We're supposed to be trying to review
>> things that were ready to go by the start of the CF, not the end.
> We are supporting v10 branch in our github repository
> https://github.com/postgrespro/sqljson/tree/sqljson_v10
>
> Since the first post we made a lot of changes, mostly because of
> better understanding the standard and availability of technical report
> (http://standards.iso.org/ittf/PubliclyAvailableStandards/c067367_ISO_IEC_TR_19075-6_2017.zip).
> Most important are:
>
> 1.We abandoned FORMAT support, which could confuse our users, since we
> have data types json[b].
>
> 2. We use XMLTABLE infrastructure, extended for JSON_TABLE support.
>
> 3. Reorganize commits, so we could split one big patch by several
> smaller patches, which could be reviewed independently.
>
> 4. The biggest problem is documentation, we are working on it.
>
> Nikita will submit patches soon.

Attached archive with 9 patches rebased onto latest master.

0001-jsonpath-v02.patch:
- jsonpath type
- jsonpath execution on jsonb type
- jsonpath operators for jsonb type
- GIN support for jsonpath operators

0002-jsonpath-json-v02.patch:
- jsonb-like iterators for json type
- jsonpath execution on json type
- jsonpath operators for json type

0003-jsonpath-extensions-v02.patch:
0004-jsonpath-extensions-tests-for-json-v02.patch:
- some useful standard extensions with tests

0005-sqljson-v02.patch:
- SQL/JSON constructors (JSON_OBJECT[AGG], JSON_ARRAY[AGG])
- SQL/JSON query functions (JSON_VALUE, JSON_QUERY, JSON_EXISTS)
- IS JSON predicate

0006-sqljson-json-v02.patch:
- SQL/JSON support for json type and tests

0007-json_table-v02.patch:
- JSON_TABLE using XMLTABLE infrastructure

0008-json_table-json-v02.patch:
- JSON_TABLE support for json type

0009-wip-extensions-v02.patch:
- FORMAT JSONB
- jsonb to/from bytea casts
- jsonpath operators
- some unfinished jsonpath extensions

Originally, JSON path was implemented only for jsonb type, and I decided to
add jsonb-like iterators for json type for json support implementation with
minimal changes in JSON path code. This solution (see jsonpath_json.c from
patch 0002) looks a little dubious to me, so I separated json support into
independent patches.

The last WIP patch 0009 is unfinished and contains a lot of FIXMEs. But
the ability to use arbitrary Postgres operators in JSON path with explicitly
specified types is rather interesting, and I think it should be shown now
to get a some kind of pre-review.

We are supporting v11 and v10 branches in our github repository:

https://github.com/postgrespro/sqljson/tree/sqljson
https://github.com/postgrespro/sqljson/tree/sqljson_wip
https://github.com/postgrespro/sqljson/tree/sqljson_v10
https://github.com/postgrespro/sqljson/tree/sqljson_v10_wip

Attached patches can be produced simply by combining groups of consecutive
commits from these branches.

--
Nikita Glukhov
Postgres Professional:http://www.postgrespro.com
The Russian Postgres Company