On Fri, May 27, 2022 at 2:08 PM Peter Smith <smithpb2...@gmail.com> wrote: > > On Fri, May 27, 2022 at 5:04 PM shiy.f...@fujitsu.com > <shiy.f...@fujitsu.com> wrote: > > > > On Wed, May 25, 2022 7:55 PM vignesh C <vignes...@gmail.com> wrote: > > > > > > The attached v16 patch has the changes for the same. > > > > > > > Thanks for updating the patch. > > > > Some comments for the document in 0002 patch. > > > > 1. > > + <para> > > + Lock the required tables in <literal>node1</literal> and > > + <literal>node2</literal> till the setup is completed. > > + </para> > > + > > + <para> > > + Create a publication in <literal>node1</literal>: > > +<programlisting> > > +node1=# CREATE PUBLICATION pub_node1 FOR TABLE t1; > > +CREATE PUBLICATION > > +</programlisting></para> > > > > If the table is locked in the very beginning, we will not be able to create > > the > > publication (because the locks have conflict). Maybe we should switch the > > order > > of creating publication and locking tables here. > > > > I agree. It seems some of the locking instructions in the earlier > sections 31.11.1 - 31.11.4 are contradictory to the later "generic" > steps given in "31.11.5. Generic steps to add a new node to the > existing set of nodes". I'm assuming the generic steps are the > "correct" steps > > e.g. generic steps say get the lock on new node tables AFTER the > publication of new node. > e.g. generic steps say do NOT get a table lock on the node one you are > (first) joining to.
Yes, the generic steps are correct. modified > ~~~ > > Furthermore, the generic steps are describing attaching a new N+1th > node to some (1 ... N) other nodes. > > So I think in the TWO-node case (section 31.11.1) node2 should be > treated as the "new" node that you are attaching to the "first" node1. > IMO the section 31.11.1 example should be reversed so that it obeys > the "generic" pattern. > e.g. It should be doing the CREATE PUBLICATION pub_node2 first (since > that is the "new" node) In generic steps we mention the publication must be created in a new node and we don't say about the existing nodes, because the publication would be existing already. I feel the existing order of publication creation in the TWO-node case (section 31.11.1) is ok. Thanks for the comments, the v17 patch attached at [1] has the changes for the same. [1] - https://www.postgresql.org/message-id/CALDaNm1rMihO7daiFyLdxkqArrC%2BdtM61oPXc-XrTYBYnJg3nw%40mail.gmail.com Regards, Vignesh
