Horton

Re: Support logical replication of DDLs

Masahiko Sawada <sawada.mshk@gmail.com>

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From: Masahiko Sawada <sawada.mshk@gmail.com>
To: Ajin Cherian <itsajin@gmail.com>
Cc: Peter Smith <smithpb2250@gmail.com>, vignesh C <vignesh21@gmail.com>, Zheng Li <zhengli10@gmail.com>, li jie <ggysxcq@gmail.com>, Dilip Kumar <dilipbalaut@gmail.com>, Alvaro Herrera <alvherre@alvh.no-ip.org>, "houzj.fnst@fujitsu.com" <houzj.fnst@fujitsu.com>, Amit Kapila <amit.kapila16@gmail.com>, Japin Li <japinli@hotmail.com>, rajesh singarapu <rajesh.rs0541@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2023-02-10T14:52:41Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add a run_as_owner option to subscriptions.

  2. Refactor pgoutput_change().

  3. Print the correct aliases for DML target tables in ruleutils.

  4. Fix object identity string for transforms

  5. Add grantable MAINTAIN privilege and pg_maintain role.

  6. Get rid of recursion-marker values in enum AlterTableType

  7. Release cache tuple when no longer needed

  8. Empty search_path in logical replication apply worker and walsender.

  9. Refactor format_type APIs to be more modular

  10. Use wrappers of PG_DETOAST_DATUM_PACKED() more.

Hi,

On Thu, Feb 9, 2023 at 6:55 PM Ajin Cherian <itsajin@gmail.com> wrote:
>
(v67)

I have some questions about adding the infrastructure for DDL deparsing.

Apart from the changes made by 0001 patch to add infrastructure for
DDL deparsing, 0002 patch seems to add some variables that are not
used in 0002 patch:

@@ -2055,6 +2055,7 @@ typedef struct AlterTableStmt
        List       *cmds;                       /* list of subcommands */
        ObjectType      objtype;                /* type of object */
        bool            missing_ok;             /* skip error if table
missing */
+       bool        table_like;         /* internally generated for
TableLikeClause */
 } AlterTableStmt;

@@ -39,6 +40,7 @@ typedef struct CollectedATSubcmd
 {
        ObjectAddress address;          /* affected column,
constraint, index, ... */
        Node       *parsetree;
+       char       *usingexpr;
 } CollectedATSubcmd;

 typedef struct CollectedCommand
@@ -62,6 +64,7 @@ typedef struct CollectedCommand
                {
                        Oid                     objectId;
                        Oid                     classId;
+                       bool            rewrite;
                        List       *subcmds;
                }                       alterTable;

These three variables are used in 0006 patch.

Looking at 0006 patch (Support DDL replication), it seems to me that
it includes not only DDL replication support but also changes for the
event trigger. For instance, the patch adds
EventTriggerAlterTypeStart() and EventTriggerAlterTypeEnd(). If these
changes are required for DDL deparse, should we include them in 0001
patch? Perhaps the same is true for
EventTriggerCollectCreatePublication() and friends. IIUC the DDL
deparse and DDL replication are independent features, so I think 0006
patch should not include any changes for DDL deparse infrastructure.

Also, 0003 and 0006 patches introduce SCT_Create/AlterPublication and
change DDL deparse so that it deparse CREATE/ALTER PUBLICATION in a
different way from other simple commands. Is there any reason for
that? I mean, since EventTriggerCollectCreatePublication() collects
the information from the parse tree, I wonder if we could use
SCT_Simple for them.

Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com