Horton

RE: row filtering for logical replication

Wei Wang (Fujitsu) <wangw.fnst@fujitsu.com>

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From: "wangw.fnst@fujitsu.com" <wangw.fnst@fujitsu.com>
To: Peter Smith <smithpb2250@gmail.com>
Cc: "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Amit Kapila <amit.kapila16@gmail.com>, Euler Taveira <euler@eulerto.com>, Greg Nancarrow <gregn4422@gmail.com>, vignesh C <vignesh21@gmail.com>, Ajin Cherian <itsajin@gmail.com>, "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>, Dilip Kumar <dilipbalaut@gmail.com>, Rahila Syed <rahilasyed90@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, Önder Kalacı <onderkalaci@gmail.com>, japin <japinli@hotmail.com>, Michael Paquier <michael@paquier.xyz>, David Steele <david@pgmasters.net>, Craig Ringer <craig@2ndquadrant.com>, Amit Langote <amitlangote09@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2022-01-05T02:05:08Z
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. Release cache tuple when no longer needed

  2. Add some additional tests for row filters in logical replication.

  3. Fix one of the tests introduced in commit 52e4f0cd47.

  4. Allow specifying row filters for logical replication of tables.

  5. Move scanint8() to numutils.c

  6. Replace Test::More plans with done_testing

  7. Reduce relcache access in WAL sender streaming logical changes

  8. Small cleanups related to PUBLICATION framework code

  9. Add a view to show the stats of subscription workers.

  10. Allow publishing the tables of schema.

  11. Doc: improve documentation of CREATE/ALTER SUBSCRIPTION.

  12. Add PublicationTable and PublicationRelInfo structs

  13. Remove unused argument "txn" in maybe_send_schema().

  14. Add prepare API support for streaming transactions in logical replication.

  15. Unify PostgresNode's new() and get_new_node() methods

  16. Use l*_node() family of functions where appropriate

  17. Add support for prepared transactions to built-in logical replication.

  18. Restore the portal-level snapshot after procedure COMMIT/ROLLBACK.

  19. Rename a parse node to be more general

  20. Remove unused column atttypmod from initial tablesync query

  21. SEARCH and CYCLE clauses

On Thu, Jan 4, 2022 at 00:54 PM Peter Smith <smithpb2250@gmail.com> wrote:
> Modified in v58 [1] as suggested
Thanks for updating the patches.
A few comments about v58-0001 and v58-0002.

v58-0001
1.
How about modifying the following loop in copy_table by using for_each_from
instead of foreach?
Like the invocation of for_each_from in function get_rule_expr.
from:
		if (qual != NIL)
		{
			ListCell   *lc;
			bool		first = true;

			appendStringInfoString(&cmd, " WHERE ");
			foreach(lc, qual)
			{
				char	   *q = strVal(lfirst(lc));

				if (first)
					first = false;
				else
					appendStringInfoString(&cmd, " OR ");
				appendStringInfoString(&cmd, q);
			}
			list_free_deep(qual);
		}
change to:
		if (qual != NIL)
		{
			ListCell   *lc;
			char	   *q = strVal(linitial(qual));

			appendStringInfo(&cmd, " WHERE %s", q);
			for_each_from(lc, qual, 1)
			{
				q = strVal(lfirst(lc));
				appendStringInfo(&cmd, " OR %s", q);
			}
			list_free_deep(qual);
		}

2.
I find the API of get_rel_sync_entry is modified. 
-get_rel_sync_entry(PGOutputData *data, Oid relid)
+get_rel_sync_entry(PGOutputData *data, Relation relation)
It looks like just moving the invocation of RelationGetRelid from outside into
function get_rel_sync_entry. I am not sure whether this modification is
necessary to this feature or not.

v58-0002
1.
In function pgoutput_row_filter_init, if no_filter is set, I think we do not
need to add row filter to list(rfnodes).
So how about changing three conditions when add row filter to rfnodes like this:
-					if (pub->pubactions.pubinsert)
+					if (pub->pubactions.pubinsert && !no_filter[idx_ins])
					{
						rfnode = stringToNode(TextDatumGetCString(rfdatum));
						rfnodes[idx_ins] = lappend(rfnodes[idx_ins], rfnode);
					}

Regards,
Wang wei