Re: Data is copied twice when specifying both child and parent table in publication
Peter Smith <smithpb2250@gmail.com>
From: Peter Smith <smithpb2250@gmail.com>
To: "wangw.fnst@fujitsu.com" <wangw.fnst@fujitsu.com>
Cc: Amit Kapila <amit.kapila16@gmail.com>, Andres Freund <andres@anarazel.de>, vignesh C <vignesh21@gmail.com>, "Takamichi Osumi (Fujitsu)" <osumi.takamichi@fujitsu.com>, "shiy.fnst@fujitsu.com" <shiy.fnst@fujitsu.com>,
"houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Amit Langote <amitlangote09@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>,
Dilip Kumar <dilipbalaut@gmail.com>, Greg Nancarrow <gregn4422@gmail.com>
Date: 2023-03-20T07:32:15Z
Lists: pgsql-hackers
Here are some review comments for v17-0001.
======
src/backend/catalog/pg_publication.c
1. filter_partitions
-static List *
-filter_partitions(List *relids)
+static void
+filter_partitions(List *table_infos)
{
- List *result = NIL;
ListCell *lc;
- ListCell *lc2;
- foreach(lc, relids)
+ foreach(lc, table_infos)
{
- bool skip = false;
- List *ancestors = NIL;
- Oid relid = lfirst_oid(lc);
+ bool skip = false;
+ List *ancestors = NIL;
+ ListCell *lc2;
+ published_rel *table_info = (published_rel *) lfirst(lc);
- if (get_rel_relispartition(relid))
- ancestors = get_partition_ancestors(relid);
+ if (get_rel_relispartition(table_info->relid))
+ ancestors = get_partition_ancestors(table_info->relid);
foreach(lc2, ancestors)
{
Oid ancestor = lfirst_oid(lc2);
+ ListCell *lc3;
/* Check if the parent table exists in the published table list. */
- if (list_member_oid(relids, ancestor))
+ foreach(lc3, table_infos)
{
- skip = true;
- break;
+ Oid relid = ((published_rel *) lfirst(lc3))->relid;
+
+ if (relid == ancestor)
+ {
+ skip = true;
+ break;
+ }
}
+
+ if (skip)
+ break;
}
- if (!skip)
- result = lappend_oid(result, relid);
+ if (skip)
+ table_infos = foreach_delete_current(table_infos, lc);
}
-
- return result;
}
It seems the 'skip' and 'ancestors' and 'lc2' vars are not needed
except when "if (get_rel_relispartition(table_info->relid))" is true,
so won't it be better to restructure the code to put everything inside
that condition. Then you will save a few unnecessary tests of
foreach(lc2, ancestors) and (skip).
For example,
static void
filter_partitions(List *table_infos)
{
ListCell *lc;
foreach(lc, table_infos)
{
published_rel *table_info = (published_rel *) lfirst(lc);
if (get_rel_relispartition(table_info->relid))
{
bool skip = false;
List *ancestors = get_partition_ancestors(table_info->relid);
ListCell *lc2;
foreach(lc2, ancestors)
{
Oid ancestor = lfirst_oid(lc2);
ListCell *lc3;
/* Check if the parent table exists in the published table list. */
foreach(lc3, table_infos)
{
Oid relid = ((published_rel *) lfirst(lc3))->relid;
if (relid == ancestor)
{
skip = true;
break;
}
}
if (skip)
break;
}
if (skip)
table_infos = foreach_delete_current(table_infos, lc);
}
}
}
~~~
2. pg_get_publication_tables
+ else
+ {
+ List *relids,
+ *schemarelids;
+
+ relids = GetPublicationRelations(pub_elem->oid,
+ pub_elem->pubviaroot ?
+ PUBLICATION_PART_ROOT :
+ PUBLICATION_PART_LEAF);
+ schemarelids = GetAllSchemaPublicationRelations(pub_elem->oid,
+ pub_elem->pubviaroot ?
+ PUBLICATION_PART_ROOT :
+ PUBLICATION_PART_LEAF);
+ pub_elem_tables = list_concat_unique_oid(relids, schemarelids);
+ }
2a.
Maybe 'schema_relids' would be a better name than 'schemareliids'?
~
2b.
By introducing another variable maybe you could remove some of this
duplicated code.
PublicationPartOpt root_or_leaf = pub_elem->pubviaroot ?
PUBLICATION_PART_ROOT : PUBLICATION_PART_LEAF;
~~~
3. pg_get_publication_tables
/* Show all columns when the column list is not specified. */
- if (nulls[1] == true)
+ if (nulls[2] == true)
Since you are changing this line anyway, you might as well change it
to remove the redundant "== true" part.
SUGGESTION
if (nulls[2])
======
src/include/catalog/pg_proc.dat
4.
+{ oid => '6119',
+ descr => 'get information of the tables in the given publication array',
Should that be worded in a way to make it more clear that the
"publication array" is really an "array of publication names"?
------
Kind Regards,
Peter Smith.
Fujitsu Australia
Commits
-
Avoid syncing data twice for the 'publish_via_partition_root' option.
- 062a84442424 16.0 landed
-
Fix partition table's REPLICA IDENTITY checking on the subscriber.
- 52d5ea9adb01 14.5 cited
-
Prohibit combining publications with different column lists.
- fd0b9dcebda7 15.0 cited
-
Fix double publish of child table's data.
- 3f06c00cf6dc 13.6 landed
- 614b77d65a38 14.2 landed
- 5e97905a2c76 15.0 landed
-
Support adding partitioned tables to publication
- 17b9e7f9fe23 13.0 cited