Re: First draft of PG 17 release notes

Bruce Momjian <bruce@momjian.us>

From: Bruce Momjian <bruce@momjian.us>

To: Andy Fan <zhihuifan1213@163.com>

Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>, pgsql-hackers@lists.postgresql.org

Date: 2024-05-15T00:37:19Z

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 →

Revert support for ALTER TABLE ... MERGE/SPLIT PARTITION(S) commands
- 3890d90c1508 18.0 cited
When creating materialized views, use REFRESH to load data.
- b4da732fd64e 17.0 cited
Revert temporal primary keys and foreign keys
- 8aee330af55d 17.0 cited
Avoid needless large memcpys in libpq socket writing
- c4ab7da60617 17.0 cited
Enhance nbtree ScalarArrayOp execution.
- 5bf748b86bc6 17.0 cited
Introduce a non-recursive JSON parser
- 3311ea86edc7 17.0 cited
Combine freezing and pruning steps in VACUUM
- 6dbb490261a6 17.0 cited
Allow SIGINT to cancel psql database reconnections.
- cafe1056558f 17.0 cited
Provide API for streaming relation data.
- b5a9b18cd0bc 17.0 cited
Add hash support functions and hash opclass for contrib/ltree.
- 485f0aa85995 17.0 cited
Pull up ANY-SUBLINK with the necessary lateral support.
- 9f133763961e 17.0 cited
Read WAL directly from WAL buffers.
- 91f2cae7a4e6 17.0 cited
Introduce the dynamic shared memory registry.
- 8b2bcf3f287c 17.0 cited
Add macros for looping through a List without a ListCell.
- 14dd0f27d7cd 17.0 cited
Support +/- infinity in the interval data type.
- 519fc1bd9e9d 17.0 cited
Extend ALTER OPERATOR to allow setting more optimization attributes.
- 2b5154beab79 17.0 cited
Consider cheap startup paths in add_paths_to_append_rel
- a8a968a8212e 17.0 cited

Attachments

master.diff (text/x-diff) patch

On Tue, May 14, 2024 at 10:32:14AM +0800, Andy Fan wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > It was unclear from the commit message exactly what user-visible
> > optimization this allowed.  Do you have details?
> 
> Yes, It allows the query like "SELECT * FROM t1 WHERE t1.a in (SELECT a
> FROM t2 WHERE t2.b = t1.b)" be pulled up a semi join, hence more join
> methods / join orders are possible.
> 
> 
> Yes, for example:  (subquery-1) UNION ALL (subquery-2) LIMIT n;
> 
> When planning the subquery-1 or subquery-2, limit N should be
> considered. As a consequence, maybe hash join should be replaced with
> Nested Loop. Before this commits, it is ignored if it is flatten into 
> appendrel, and the "flatten" happens very often.
> 
> David provided a summary for the both commits in [1].

Okay, attached patch applied.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Only you can decide what is important to you.