Re: logical replication empty transactions

On Mon, Apr 26, 2021 at 4:29 PM Peter Smith <smithpb2250(at)gmail(dot)com> wrote:

> The v4 patch applied cleanly.
>
> make check-world completed successfully.
>
> So this patch v4 looks LGTM, apart from the following 2 nitpick comments:
>
> ======
>
> 1. Suggest to add a blank line after the (void)txn; ?
>
> @@ -345,10 +345,29 @@ pgoutput_startup(LogicalDecodingContext *ctx,
> OutputPluginOptions *opt,
> static void
> pgoutput_begin_txn(LogicalDecodingContext *ctx, ReorderBufferTXN *txn)
> {
> + PGOutputData *data = (PGOutputData *) ctx->output_plugin_private;
> +
> + (void)txn; /* keep compiler quiet */
> + /*
> + * Don't send BEGIN message here. Instead, postpone it until the first
>
>

Fixed.

> ======
>
> 2. Unnecessary statement blocks?
>
> AFAIK those { } are not the usual PG code-style when there is only one
> statement, so suggest to remove them.
>
> Appies to 3 places:
>
> @@ -551,6 +576,12 @@ pgoutput_change(LogicalDecodingContext *ctx,
> ReorderBufferTXN *txn,
> Assert(false);
> }
>
> + /* output BEGIN if we haven't yet */
> + if (!data->sent_begin_txn && !in_streaming)
> + {
> + pgoutput_begin(ctx, txn);
> + }
>
> @@ -693,6 +724,12 @@ pgoutput_truncate(LogicalDecodingContext *ctx,
> ReorderBufferTXN *txn,
>
> if (nrelids > 0)
> {
> + /* output BEGIN if we haven't yet */
> + if (!data->sent_begin_txn && !in_streaming)
> + {
> + pgoutput_begin(ctx, txn);
> + }
>
> @@ -725,6 +762,12 @@ pgoutput_message(LogicalDecodingContext *ctx,
> ReorderBufferTXN *txn,
> if (in_streaming)
> xid = txn->xid;
>
> + /* output BEGIN if we haven't yet, avoid for streaming and
> non-transactional messages */
> + if (!data->sent_begin_txn && !in_streaming && transactional)
> + {
> + pgoutput_begin(ctx, txn);
> + }
>

Fixed.

regards,
Ajin Cherian
Fujitsu Australia