Horton

RE: row filtering for logical replication

Zhijie Hou (Fujitsu) <houzj.fnst@fujitsu.com>

View thread
From: "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>
To: Peter Smith <smithpb2250@gmail.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, "tanghy.fnst@fujitsu.com" <tanghy.fnst@fujitsu.com>, Euler Taveira <euler@eulerto.com>, Greg Nancarrow <gregn4422@gmail.com>, vignesh C <vignesh21@gmail.com>, Ajin Cherian <itsajin@gmail.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: 2022-01-17T15:30:00Z
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 Mon, Jan 17, 2022 12:34 PM Peter Smith <smithpb2250@gmail.com> wrote:
> 
> Here are some review comments for v65-0001 (review of updates since
> v64-0001)

Thanks for the comments!

> ~~~
> 
> 1. src/include/commands/publicationcmds.h - rename func
> 
> +extern bool contain_invalid_rfcolumn(Oid pubid, Relation relation,
> +List *ancestors,  AttrNumber *invalid_rfcolumn);
> 
> I thought that function should be called "contains_..." instead of "contain_...".
> 
> ~~~
> 
> 2. src/backend/commands/publicationcmds.c - rename funcs
> 
> Suggested renaming (same as above #1).
> 
> "contain_invalid_rfcolumn_walker" --> "contains_invalid_rfcolumn_walker"
> "contain_invalid_rfcolumn" --> "contains_invalid_rfcolumn"
> 
> Also, update it in the comment for rf_context:
> +/*
> + * Information used to validate the columns in the row filter
> +expression. See
> + * contain_invalid_rfcolumn_walker for details.
> + */

I am not sure about the name because many existing
functions are named contain_xxx_xxx.
(for example contain_mutable_functions)

> 
> 3. src/backend/commands/publicationcmds.c - bms
> 
> + if (!rfisnull)
> + {
> + rf_context context = {0};
> + Node    *rfnode;
> + Bitmapset    *bms = NULL;
> +
> + context.pubviaroot = pub->pubviaroot;
> + context.parentid = publish_as_relid;
> + context.relid = relid;
> +
> + /*
> + * Remember columns that are part of the REPLICA IDENTITY. Note that
> + * REPLICA IDENTITY DEFAULT means primary key or nothing.
> + */
> + if (relation->rd_rel->relreplident == REPLICA_IDENTITY_DEFAULT) bms =
> + RelationGetIndexAttrBitmap(relation,
> + INDEX_ATTR_BITMAP_PRIMARY_KEY);
> + else if (relation->rd_rel->relreplident == REPLICA_IDENTITY_INDEX) bms
> + = RelationGetIndexAttrBitmap(relation,
> + INDEX_ATTR_BITMAP_IDENTITY_KEY);
> +
> + context.bms_replident = bms;
> 
> There seems no need for a separate 'bms' variable here. Why not just assign
> directly to context.bms_replident like the code used to do?

Because I found it made the code exceed 80 cols, so I personally
think use a shorter variable could make it looks better.

> 
> 4. src/backend/utils/cache/relcache.c - typo?
> 
>   /*
> - * If we know everything is replicated, there is no point to check for
> - * other publications.
> + * Check, if all columns referenced in the filter expression are part
> + * of the REPLICA IDENTITY index or not.
> + *
> + * If we already found the column in row filter which is not part of
> + * REPLICA IDENTITY index, skip the validation.
>   */
> 
> Shouldn't that comment say "already found a column" instead of "already found
> the column"?

Adjusted the comments here. 

> 
> 5. src/backend/replication/pgoutput/pgoutput.c - map member
> 
> @@ -129,7 +169,7 @@ typedef struct RelationSyncEntry
>   * same as 'relid' or if unnecessary due to partition and the ancestor
>   * having identical TupleDesc.
>   */
> - TupleConversionMap *map;
> + AttrMap *map;
>  } RelationSyncEntry;
> 
> I wondered if you should also rename this member to something more
> meaningful like 'attrmap' instead of just 'map'.
Changed.

Best regards,
Hou zj