Re: row filtering for logical replication

On Tue, Feb 1, 2022 at 2:45 PM houzj.fnst@fujitsu.com
<houzj.fnst@fujitsu.com> wrote:
>
> Attach the V75 patch set which address the above, Amit's[1] and Greg's[2][3] comments.
>

In the v74-0001 patch (and now in the v75-001 patch) a change was made
in the GetTopMostAncestorInPublication() function, to get the relation
and schema publications lists (for the ancestor Oid) up-front:

+ List    *apubids = GetRelationPublications(ancestor);
+ List    *aschemaPubids = GetSchemaPublications(get_rel_namespace(ancestor));
+
+ if (list_member_oid(apubids, puboid) ||
+    list_member_oid(aschemaPubids, puboid))
+       topmost_relid = ancestor;

However, it seems that this makes it less efficient in the case a
match is found in the first list that is searched, since then there
was actually no reason to create the second list.
Instead of this, how about something like this:

List    *apubids = GetRelationPublications(ancestor);
List    *aschemaPubids = NULL;

if (list_member_oid(apubids, puboid) ||
   list_member_oid(aschemaPubids =
GetSchemaPublications(get_rel_namespace(ancestor)), puboid))
      topmost_relid = ancestor;

or, if that is considered a bit ugly due to the assignment within the
function parameters, alternatively:

List    *apubids = GetRelationPublications(ancestor);
List    *aschemaPubids = NULL;

if (list_member_oid(apubids, puboid))
   topmost_relid = ancestor;
else
{
   aschemaPubids = GetSchemaPublications(get_rel_namespace(ancestor));
   if (list_member_oid(aschemaPubids, puboid))
      topmost_relid = ancestor;
}

Regards,
Greg Nancarrow
Fujitsu Australia