On Fri, 15 Nov 2024 at 20:31, vignesh C <vignes...@gmail.com> wrote:
>
> On Fri, 15 Nov 2024 at 16:45, Shlok Kyal <shlok.kyal....@gmail.com> wrote:
> >
> > Thanks for providing the comments
> >
> > On Fri, 15 Nov 2024 at 10:59, vignesh C <vignes...@gmail.com> wrote:
> > >
> > > On Thu, 14 Nov 2024 at 15:51, Shlok Kyal <shlok.kyal....@gmail.com> wrote:
> > > >
> > > > Thanks for providing the comments.
> > > >
> > > > On Thu, 14 Nov 2024 at 12:22, vignesh C <vignes...@gmail.com> wrote:
> > > > >
> > > > > On Wed, 13 Nov 2024 at 11:15, Shlok Kyal <shlok.kyal....@gmail.com> 
> > > > > wrote:
> > > > > >
> > > > > > Thanks for providing the comments.
> > > > > >
> > > > > > On Tue, 12 Nov 2024 at 12:52, Zhijie Hou (Fujitsu)
> > > > > > <houzj.f...@fujitsu.com> wrote:
> > > > > > >
> > > > > > > On Friday, November 8, 2024 7:06 PM Shlok Kyal 
> > > > > > > <shlok.kyal....@gmail.com> wrote:
> > > > > > > >
> > > > > > > > Hi Amit,
> > > > > > > >
> > > > > > > > On Thu, 7 Nov 2024 at 11:37, Amit Kapila 
> > > > > > > > <amit.kapil...@gmail.com> wrote:
> > > > > > > > >
> > > > > > > > > On Tue, Nov 5, 2024 at 12:53 PM Shlok Kyal 
> > > > > > > > > <shlok.kyal....@gmail.com>
> > > > > > > > wrote:
> > > > > > > > > >
> > > > > > > > > > To avoid the issue, we can disallow UPDATE/DELETE on table 
> > > > > > > > > > with
> > > > > > > > > > unpublished generated column as REPLICA IDENTITY. I have 
> > > > > > > > > > attached a
> > > > > > > > > > patch for the same.
> > > > > > > > > >
> > > > > > > > >
> > > > > > > > > +CREATE PUBLICATION pub_gencol FOR TABLE testpub_gencol; 
> > > > > > > > > UPDATE
> > > > > > > > > +testpub_gencol SET a = 100 WHERE a = 1;
> > > > > > > > > +ERROR:  cannot update table "testpub_gencol"
> > > > > > > > > +DETAIL:  Column list used by the publication does not cover 
> > > > > > > > > the
> > > > > > > > > replica identity.
> > > > > > > > >
> > > > > > > > > This is not a correct ERROR message as the publication 
> > > > > > > > > doesn't have
> > > > > > > > > any column list associated with it. You have added the code 
> > > > > > > > > to detect
> > > > > > > > > this in the column list code path which I think is not 
> > > > > > > > > required. BTW,
> > > > > > > > > you also need to consider the latest commit 7054186c4e for 
> > > > > > > > > this. I
> > > > > > > > > guess you need to keep another flag in PublicationDesc to 
> > > > > > > > > detect this
> > > > > > > > > and then give an appropriate ERROR.
> > > > > > > >
> > > > > > > > I have addressed the comments and provided an updated patch. 
> > > > > > > > Also, I am
> > > > > > > > currently working to fix this issue in back branches.
> > > > > > >
> > > > > > > Thanks for the patch. I am reviewing it and have some initial 
> > > > > > > comments:
> > > > > > >
> > > > > > >
> > > > > > > 1.
> > > > > > > +                       char attgenerated = 
> > > > > > > get_attgenerated(relid, attnum);
> > > > > > > +
> > > > > > >
> > > > > > > I think it's unnecessary to initialize attgenerated here because 
> > > > > > > the value will
> > > > > > > be overwritten if pubviaroot is true anyway. Also, the 
> > > > > > > get_attgenerated()
> > > > > > > is not cheap.
> > > > > > >
> > > > > > Fixed
> > > > > >
> > > > > > > 2.
> > > > > > >
> > > > > > > I think the patch missed to check the case when table is marked 
> > > > > > > REPLICA
> > > > > > > IDENTITY FULL, and generated column is not published:
> > > > > > >
> > > > > > > CREATE TABLE testpub_gencol (a INT, b INT GENERATED ALWAYS AS (a 
> > > > > > > + 1) STORED NOT NULL);
> > > > > > > ALTER TABLE testpub_gencol REPLICA IDENTITY FULL;
> > > > > > > CREATE PUBLICATION pub_gencol FOR TABLE testpub_gencol;
> > > > > > > UPDATE testpub_gencol SET a = 2;
> > > > > > >
> > > > > > > I expected the UPDATE to fail in above case, but it can still 
> > > > > > > pass after applying the patch.
> > > > > > >
> > > > > > Fixed
> > > > > >
> > > > > > > 3.
> > > > > > >
> > > > > > > +                * If the publication is FOR ALL TABLES we can 
> > > > > > > skip the validation.
> > > > > > > +                */
> > > > > > >
> > > > > > > This comment seems not clear to me, could you elaborate a bit 
> > > > > > > more on this ?
> > > > > > >
> > > > > > I missed to handle the case FOR ALL TABLES. Have removed the 
> > > > > > comment.
> > > > > >
> > > > > > > 4.
> > > > > > >
> > > > > > > Also, I think the patch does not handle the FOR ALL TABLE case 
> > > > > > > correctly:
> > > > > > >
> > > > > > > CREATE TABLE testpub_gencol (a INT, b INT GENERATED ALWAYS AS (a 
> > > > > > > + 1) STORED NOT NULL);
> > > > > > > CREATE UNIQUE INDEX testpub_gencol_idx ON testpub_gencol (b);
> > > > > > > ALTER TABLE testpub_gencol REPLICA IDENTITY USING index 
> > > > > > > testpub_gencol_idx;
> > > > > > > CREATE PUBLICATION pub_gencol FOR ALL TABLEs;
> > > > > > > UPDATE testpub_gencol SET a = 2;
> > > > > > >
> > > > > > > I expected the UPDATE to fail in above case as well.
> > > > > > >
> > > > > > Fixed
> > > > > >
> > > > > > > 5.
> > > > > > >
> > > > > > > +       else if (cmd == CMD_UPDATE && 
> > > > > > > !pubdesc.replident_has_valid_gen_cols)
> > > > > > > +               ereport(ERROR,
> > > > > > > +                               
> > > > > > > (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
> > > > > > > +                                errmsg("cannot update table 
> > > > > > > \"%s\"",
> > > > > > > +                                               
> > > > > > > RelationGetRelationName(rel)),
> > > > > > > +                                errdetail("REPLICA IDENTITY 
> > > > > > > consists of an unpublished generated column.")));
> > > > > > >
> > > > > > > I think it would be better to use lower case "replica identity" 
> > > > > > > to consistent
> > > > > > > with other existing messages.
> > > > > > >
> > > > > > Fixed
> > > > > >
> > > > > > I have attached the updated patch here.
> > > > >
> > > > > Few comments:
> > > > > 1) In the first check relation->rd_rel->relispartition also is checked
> > > > > whereas in the below it is not checked, shouldn't the same check be
> > > > > there below to avoid few of the function calls which are not required:
> > > > > +       if (pubviaroot && relation->rd_rel->relispartition)
> > > > > +       {
> > > > > +               publish_as_relid =
> > > > > GetTopMostAncestorInPublication(pubid, ancestors, NULL);
> > > > > +
> > > > > +               if (!OidIsValid(publish_as_relid))
> > > > > +                       publish_as_relid = relid;
> > > > > +       }
> > > > > +
> > > > >
> > > > > +                       if (pubviaroot)
> > > > > +                       {
> > > > > +                               /* attribute name in the child table 
> > > > > */
> > > > > +                               char       *colname =
> > > > > get_attname(relid, attnum, false);
> > > > > +
> > > > > +                               /*
> > > > > +                                * Determine the attnum for the
> > > > > attribute name in parent (we
> > > > > +                                * are using the column list defined
> > > > > on the parent).
> > > > > +                                */
> > > > > +                               attnum = get_attnum(publish_as_relid, 
> > > > > colname);
> > > > > +                               attgenerated =
> > > > > get_attgenerated(publish_as_relid, attnum);
> > > > > +                       }
> > > > > +                       else
> > > > > +                               attgenerated = 
> > > > > get_attgenerated(relid, attnum);
> > > > I have updated the if condititon
> > > >
> > > > > 2) I think we could use check_and_fetch_column_list to see that it is
> > > > > not a column list publication instead of below code:
> > > > > +       if (!puballtables)
> > > > > +       {
> > > > > +               tuple = SearchSysCache2(PUBLICATIONRELMAP,
> > > > > +
> > > > > ObjectIdGetDatum(publish_as_relid),
> > > > > +
> > > > > ObjectIdGetDatum(pubid));
> > > > > +
> > > > > +               if (!HeapTupleIsValid(tuple))
> > > > > +                       return false;
> > > > > +
> > > > > +               (void) SysCacheGetAttr(PUBLICATIONRELMAP, tuple,
> > > > > +
> > > > > Anum_pg_publication_rel_prattrs,
> > > > > +                                                          &isnull);
> > > > > +
> > > > > +               ReleaseSysCache(tuple);
> > > > > +       }
> > > > > +
> > > > > +       if(puballtables || isnull)
> > > >
> > > > Yes we can use it. I have updated the patch.
> > > >
> > > > > 3) Since there is only a single statement, remove the enclosing 
> > > > > parenthisis:
> > > > > +               if (!pubform->pubgencols &&
> > > > > +                       (pubform->pubupdate || pubform->pubdelete) &&
> > > > > +                       replident_has_unpublished_gen_col(pubid,
> > > > > relation, ancestors,
> > > > > +
> > > > >                    pubform->pubviaroot, pubform->puballtables))
> > > > > +               {
> > > > > +                       pubdesc->replident_has_valid_gen_cols = false;
> > > > > +               }
> > > > >
> > > > Fixed
> > > >
> > > > > 4) Pgindent should be run there are few issues:
> > > > > 4.a)
> > > > > +extern bool replident_has_unpublished_gen_col(Oid pubid, Relation 
> > > > > relation,
> > > > > +
> > > > >                          List *ancestors, bool pubviaroot, bool
> > > > > puballtables);
> > > > > 4.b)
> > > > > +       }
> > > > > +
> > > > > +       if(puballtables || isnull)
> > > > > +       {
> > > > > +               int                     x;
> > > > > +               Bitmapset  *idattrs = NULL;
> > > > > 4.c)
> > > > > +                * generated column we should error out.
> > > > > +                */
> > > > > +               if(relation->rd_rel->relreplident == 
> > > > > REPLICA_IDENTITY_FULL &&
> > > > > +                  relation->rd_att->constr &&
> > > > > relation->rd_att->constr->has_generated_stored)
> > > > > +                       result = true;
> > > > > 4.d)
> > > > > +               while ((x = bms_next_member(idattrs, x)) >= 0)
> > > > > +               {
> > > > > +                       AttrNumber      attnum = (x +
> > > > > FirstLowInvalidHeapAttributeNumber);
> > > > > +                       char attgenerated;
> > > > >
> > > > Fixed
> > > >
> > > > > 5) You could do this in a single line comment:
> > > > > +               /*
> > > > > +                * Check if any REPLICA IDENTITY column is an 
> > > > > generated column.
> > > > > +                */
> > > > > +               while ((x = bms_next_member(idattrs, x)) >= 0)
> > > > >
> > > >
> > > > Fixed
> > > >
> > > > > 6) I felt one of update or delete is enough in this case as the code
> > > > > path is same:
> > > > > +UPDATE testpub_gencol SET a = 100 WHERE a = 1;
> > > > > +DELETE FROM testpub_gencol WHERE a = 100;
> > > > > +
> > > > > +-- error - generated column "b" is not published and REPLICA IDENTITY
> > > > > is set FULL
> > > > > +ALTER TABLE testpub_gencol REPLICA IDENTITY FULL;
> > > > > +UPDATE testpub_gencol SET a = 100 WHERE a = 1;
> > > > > +DELETE FROM testpub_gencol WHERE a = 100;
> > > > > +DROP PUBLICATION pub_gencol;
> > > > > +
> > > > > +-- ok - generated column "b" is published and is part of REPLICA 
> > > > > IDENTITY
> > > > > +CREATE PUBLICATION pub_gencol FOR TABLE testpub_gencol with
> > > > > (publish_generated_columns = true);
> > > > > +UPDATE testpub_gencol SET a = 100 WHERE a = 1;
> > > > > +DELETE FROM testpub_gencol WHERE a = 100;
> > > >
> > > > Removed the 'DELETE' case.
> > > >
> > > > I have addressed the comments and updated the patch.
> > >
> > > Few comments:
> > > 1) Current patch will not handle this scenario where subset of columns
> > > are specified in the replica identity index:
> > > CREATE TABLE t1 (a INT not null, a1 int not null, a2 int not null, b
> > > INT GENERATED ALWAYS AS (a + 1) STORED NOT NULL);
> > > create unique index idx1_t1 on t1(a, a1);
> > >
> > > -- Replica identity will have subset of table columns
> > > alter table t1 replica identity using index idx1_t1 ;
> > > insert into t1 values(1,1,1);
> > > create publication pub1 for table t1;
> > >
> > > postgres=# update t1 set a = 2;
> > > UPDATE 1
> > >
> > > I felt we should throw an error in this case too.
> > >
> > I feel the above behaviour is expected. I think we can specify a
> > subset of columns in the replica identity index as per documentation
> > [1]. Thoughts?
> >
> > > 2) Instead of checking if replica identity has a generated column, can
> > > we check if the columns that will be published and the columns in the
> > > replica identity matches:
> > > +                       if (pubviaroot && 
> > > relation->rd_rel->relispartition)
> > > +                       {
> > > +                               /* attribute name in the child table */
> > > +                               char       *colname =
> > > get_attname(relid, attnum, false);
> > > +
> > > +                               /*
> > > +                                * Determine the attnum for the
> > > attribute name in parent (we
> > > +                                * are using the column list defined
> > > on the parent).
> > > +                                */
> > > +                               attnum = get_attnum(publish_as_relid, 
> > > colname);
> > > +                               attgenerated =
> > > get_attgenerated(publish_as_relid, attnum);
> > > +                       }
> > > +                       else
> > > +                               attgenerated = get_attgenerated(relid, 
> > > attnum);
> > >
> > Fixed
> >
> > > 3) publish_as_relid will be set accordingly based on pubviaroot, so it
> > > need not be initialized:
> > > +       Oid                     relid = RelationGetRelid(relation);
> > > +       Oid                     publish_as_relid = 
> > > RelationGetRelid(relation);
> > > +       bool            result = false;
> > >
> > Fixed
> >
> > I have addressed the comments and attached the updated patch.
>
> Few comments:
> 1) I felt we can return from here after identifying it is replica
> identity full instead of processing further:
> +               /*
> +                * REPLICA IDENTITY can be FULL only if there is no
> column list for
> +                * publication. If REPLICA IDENTITY is set as FULL and
> relation has a
> +                * generated column we should error out.
> +                */
> +               if (relation->rd_rel->relreplident == REPLICA_IDENTITY_FULL &&
> +                       relation->rd_att->constr &&
> +                       relation->rd_att->constr->has_generated_stored)
> +                       result = true;
>
> 2) columns bms also should be freed here:
>                      /* replica identity column, not covered by the
> column list */
> +                       if (!bms_is_member(attnum, columns))
> +                       {
> +                               result = true;
> +                               break;
> +                       }
> +               }
> +
> +               bms_free(idattrs);
>
> 3) Error detail message should begin with upper case:
> 3.a)
> @@ -809,6 +809,12 @@ CheckCmdReplicaIdentity(Relation rel, CmdType cmd)
>                                  errmsg("cannot update table \"%s\"",
>                                                 RelationGetRelationName(rel)),
>                                  errdetail("Column list used by the
> publication does not cover the replica identity.")));
> +       else if (cmd == CMD_UPDATE && !pubdesc.replident_has_valid_gen_cols)
> +               ereport(ERROR,
> +                               (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
> +                                errmsg("cannot update table \"%s\"",
> +                                               RelationGetRelationName(rel)),
> +                                errdetail("replica identity consists
> of an unpublished generated column.")));
>         else if (cmd == CMD_DELETE && !pubdesc.rf_valid_for_delete)
>                 ereport(ERROR,
>                                 (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
>
> 3.b) Similarly here too:
>                                  errdetail("Column list used by the
> publication does not cover the replica identity.")));
> +       else if (cmd == CMD_DELETE && !pubdesc.replident_has_valid_gen_cols)
> +               ereport(ERROR,
> +                               (errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
> +                                errmsg("cannot delete from table \"%s\"",
> +                                               RelationGetRelationName(rel)),
> +                                errdetail("replica identity consists
> of an unpublished generated column.")));
>
Thanks for providing the comments. I have fixed all the comments and
attached the updated patch.

Thanks and Regards,
Shlok Kyal

Attachment: v6-0001-Disallow-UPDATE-DELETE-on-table-with-generated-co.patch
Description: Binary data

Reply via email to