RE: Skipping logical replication transactions on subscriber side

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

From: "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>

To: Masahiko Sawada <sawada.mshk@gmail.com>

Cc: Alexey Lesovsky <lesovsky@gmail.com>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Amit Kapila <amit.kapila16@gmail.com>

Date: 2021-08-04T04:02:52Z

Lists: pgsql-hackers

On Tuesday, August 3, 2021 2:49 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> 
> I've attached new patches that incorporate all comments I got so far.
> Please review them.

Hi,

I had a few comments for the 0003 patch.

1).
-      This clause alters parameters originally set by
-      <xref linkend="sql-createsubscription"/>.  See there for more
-      information.  The parameters that can be altered
-      are <literal>slot_name</literal>,
-      <literal>synchronous_commit</literal>,
-      <literal>binary</literal>, and
-      <literal>streaming</literal>.
+      This clause sets or resets a subscription option. The parameters that can be
+      set are the parameters originally set by <xref linkend="sql-createsubscription"/>:
+      <literal>slot_name</literal>, <literal>synchronous_commit</literal>,
+      <literal>binary</literal>, <literal>streaming</literal>.
+     </para>
+     <para>
+       The parameters that can be reset are: <literal>streaming</literal>,
+       <literal>binary</literal>, <literal>synchronous_commit</literal>.

Maybe the doc looks better like the following ?

+      This clause alters parameters originally set by
+      <xref linkend="sql-createsubscription"/>.  See there for more
+      information.  The parameters that can be set
+      are <literal>slot_name</literal>,
+      <literal>synchronous_commit</literal>,
+      <literal>binary</literal>, and
+      <literal>streaming</literal>.
+     </para>
+     <para>
+       The parameters that can be reset are: <literal>streaming</literal>,
+       <literal>binary</literal>, <literal>synchronous_commit</literal>.

2).
-           opts->create_slot = defGetBoolean(defel);
+           if (!is_reset)
+               opts->create_slot = defGetBoolean(defel);
        }

Since we only support RESET streaming/binary/synchronous_commit, it
might be unnecessary to add the check 'if (!is_reset)' for other
option.

3).
typedef struct AlterSubscriptionStmt
{
    NodeTag     type;
    AlterSubscriptionType kind; /* ALTER_SUBSCRIPTION_OPTIONS, etc */

Since the patch change the remove the enum value
'ALTER_SUBSCRIPTION_OPTIONS', it'd better to change the comment here
as well.

Best regards,
houzj

Commits

Test ALIGNOF_DOUBLE==4 compatibility under ALIGNOF_DOUBLE==8.
- c1da0acbb06e 15.0 landed
Reorder subskiplsn in pg_subscription to avoid alignment issues.
- 79b716cfb7a1 15.0 landed
Add ALTER SUBSCRIPTION ... SKIP.
- 208c5d65bbd6 15.0 landed
Optionally disable subscriptions on error.
- 705e20f8550c 15.0 cited
Update docs of logical replication for commit 8d74fc96db.
- 85c61ba8920b 15.0 landed
Respect permissions within logical replication.
- a2ab9c06ea15 15.0 cited
Fix regression test failure caused by commit 8d74fc96db.
- 41e66fee0516 15.0 landed
Add a view to show the stats of subscription workers.
- 8d74fc96db5f 15.0 landed
Add logical change details to logical replication worker errcontext.
- abc0910e2e0a 15.0 landed
Rename LOGICAL_REP_MSG_STREAM_END to LOGICAL_REP_MSG_STREAM_STOP.
- 4cd7a1896871 15.0 landed
Fix typo in protocol.sgml.
- e1915646658d 14.0 landed
- 0ac1aee0d7d8 15.0 landed
Remove unused argument in apply_handle_commit_internal().
- f4b939f1a372 14.0 landed
- 16bd4becee32 15.0 landed
Fix replication of in-progress transactions in tablesync worker.
- 0926e96c4934 14.0 cited
Reorder pg_sequence columns to avoid alignment issue
- f3b421da5f4a 10.0 cited