On Mon, Apr 27, 2026 at 11:45 AM Dilip Kumar <[email protected]> wrote: > > On Tue, Apr 21, 2026 at 4:45 AM Masahiko Sawada <[email protected]> wrote: > > > > The overall idea of the previous patch set was to implement DDL > > deparsing and utilize it for DDL replication. It converted a parse > > tree into a JSON string. For instance, if a user executes "DROP TABLE > > t1", the deparser generates from its parse tree: > > > > {DROPSTMT :objects (("t1")) :removeType 41 :behavior 0 :missing_ok > > false :concurrent false} > > > > to: > > > > {"fmt": "DROP TABLE %{objidentity}s", "objidentity": "public.t1"} > > > > This JSON string is self-documenting, meaning someone who gets it can > > easily reconstruct the original DDL with schema-qualified object > > names. In a dedicated event trigger for logical replication, we > > deparsed the parse tree of a DDL, wrote it into a WAL record, and then > > the logical decoding processed it similarly to DML changes. > > I think there was also a discussion on whether to use JSON vs the > existing infrastructure of converting nodes to strings. Although the > JSON is standard format and might provide more flexibility using > existing format avoid extra maintence burden. >
Yes, the discussion related to node-to-string and the pros and cons of the deparse approach are detailed in email [1]. I think some of these points could be also related to the new approach as well. [1] - https://www.postgresql.org/message-id/OS0PR01MB571684CBF660D05B63B4412C94AB9%40OS0PR01MB5716.jpnprd01.prod.outlook.com -- With Regards, Amit Kapila.
