Обсуждение: pg_restore 14 skips ACL COLUMN when --schema is used

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pg_restore 14 skips ACL COLUMN when --schema is used

От
Kong Man
Дата:
pg_restore --schema in our script used to work well against pg_restore 10.  Now that we are on PostgreSQL 14.  pg_restore 14 skips ACL COLUMN, but not ACL TABLE, when --schema is used.

If there has been a known bug, please help direct me there for any possible workaround.

Thanks,
-Kong

pg_restore --list $dumpfile >$tocfile
pg_restore --use-list=<(grep "ACL public COLUMN event.id" $tocfile) -f - $dumpfile
--
-- PostgreSQL database dump
--

-- Dumped from database version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)
-- Dumped by pg_dump version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)

SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;

--
-- Name: COLUMN event.id; Type: ACL; Schema: public; Owner: admin
--

GRANT SELECT(id) ON TABLE public.event TO warranty_creation_verification;
GRANT SELECT(id) ON TABLE public.event TO data_reader;
GRANT SELECT(id) ON TABLE public.event TO internal_reader;


--
-- PostgreSQL database dump complete
--

pg_restore --schema=public --use-list=<(grep "ACL public COLUMN event.id" $tocfile) -f - $dumpfile
--
-- PostgreSQL database dump
--

-- Dumped from database version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)
-- Dumped by pg_dump version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)

SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;

--
-- PostgreSQL database dump complete
--

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Tom Lane
Дата:
Kong Man <kong_mansatiansin@hotmail.com> writes:
> pg_restore --schema in our script used to work well against pg_restore 10.  Now that we are on PostgreSQL 14.
pg_restore14 skips ACL COLUMN, but not ACL TABLE, when --schema is used. 

That's not the behavior I'm seeing.  Would you mind providing a
*complete* reproducer, not some fragments?

The behavior I'm seeing is that neither a TABLE nor a COLUMN ACL
will be restored, because (since v11) ACLs are restored only
if their table is restored, and the --use-list option you are
using excludes the table.

We could perhaps imagine special-casing that, but I think it would be
a wart, because for every other kind of object --use-list can only
filter stuff out, not filter it in.  (That is, if you are using
--use-list along with other selectivity options, an object must pass
both restrictions to be output.  I don't want to make --use-list
override other rules just for ACLs.)

It would be interesting to see your actual use-case, because
I suspect you may be doing something that there's a better way
to do now.  What set of objects are you trying to extract?

            regards, tom lane



Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Kong Man
Дата:
Tom,
You are right.  'Neither a TABLE nor a COLUMN ACL' are pg_restore-d, when I use -n or --schema without the TABLE toc entry.

Not knowing the behavioral change to pg_restore since PG11, I struggled to search for the root cause and made a wrong assumption based on the end result from my script.

What I do in my dbsnapshot script (to build DB baselines at each release cycle for DevOps) is (1) to pg_restore using only relevant SCHEMA toc entries, then (2) with pg_restore -n to scope out only relevant schemas it restores everything from $dumpfile.  It has been working well on PG10 for several years until we upgraded a few months ago.

Step 2 there should have included the 'public.event' table (that I showed in the previous message), because the table actually got restored with the table privileges.  I still struggle to find out why the column privileges are still missing.

Here are some simplified snippets from my script.

tocfile=/tmp/DBA-710.toc
dumpfile=/tmp/DBA-710.dump
pg_restore --list $dumpfile >$tocfile

DB=appdb
SCHEMAS=(public appschema1 appschema2)
exclusion='londiste|POLICY|PUBLICATION TABLE'
restopts=(-d "service=target dbname=$DB")

Log "[$DB]" "    restore SCHEMAs: "$(IFS='|'; cat <<<"${SCHEMAS[*]}")
pg_restore "${restopts[@]}" \
  --use-list=<(grep -A1 SCHEMA $tocfile|   # only relevant SCHEMA & ACL SCHEMA entries
               grep -E "\s("$(IFS='|'; cat <<<"${SCHEMAS[*]}")")\s") \
  $dumpfile

restopts+=($(printf " -n %s" ${SCHEMAS[@]}))  # Scope out for only relevant schemas
Log "[$DB]" "    restore data definitions"
pg_restore "${restopts[@]}" \
  --use-list=<(grep -Ev "$exclusion" $tocfile) \
  $dumpfile

Thanks,
-Kong

From: Tom Lane <tgl@sss.pgh.pa.us>
Sent: Friday, July 28, 2023 8:24 PM
To: Kong Man <kong_mansatiansin@hotmail.com>
Cc: pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: pg_restore 14 skips ACL COLUMN when --schema is used
 
Kong Man <kong_mansatiansin@hotmail.com> writes:
> pg_restore --schema in our script used to work well against pg_restore 10.  Now that we are on PostgreSQL 14.  pg_restore 14 skips ACL COLUMN, but not ACL TABLE, when --schema is used.

That's not the behavior I'm seeing.  Would you mind providing a
*complete* reproducer, not some fragments?

The behavior I'm seeing is that neither a TABLE nor a COLUMN ACL
will be restored, because (since v11) ACLs are restored only
if their table is restored, and the --use-list option you are
using excludes the table.

We could perhaps imagine special-casing that, but I think it would be
a wart, because for every other kind of object --use-list can only
filter stuff out, not filter it in.  (That is, if you are using
--use-list along with other selectivity options, an object must pass
both restrictions to be output.  I don't want to make --use-list
override other rules just for ACLs.)

It would be interesting to see your actual use-case, because
I suspect you may be doing something that there's a better way
to do now.  What set of objects are you trying to extract?

                        regards, tom lane

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Kong Man
Дата:
In this example, I generate the public.event table's ToC entries for TABLE, ACL TABLE, and ACL COLUMN, then use the result on --use-list.  pg_restore generates only the CREATE TABLE and GRANTs statements at the table, but not the column, level.

grep -P "TABLE public event\b|ACL public (COLUMN|TABLE) event\b" $tocfile

1640; 1259 23161 TABLE public event admin
10023; 0 0 ACL public TABLE event admin
10024; 0 0 ACL public COLUMN event.id admin
10025; 0 0 ACL public COLUMN event.event_notification_id admin
10026; 0 0 ACL public COLUMN event.type admin
10027; 0 0 ACL public COLUMN event.version admin
10028; 0 0 ACL public COLUMN event.partner_id admin
10029; 0 0 ACL public COLUMN event.object_id admin
10030; 0 0 ACL public COLUMN event.data admin
10031; 0 0 ACL public COLUMN event.reference_id1 admin
10032; 0 0 ACL public COLUMN event.reference_id2 admin
10033; 0 0 ACL public COLUMN event.reference_id3 admin
10034; 0 0 ACL public COLUMN event.updated admin
10035; 0 0 ACL public COLUMN event.created admin
10036; 0 0 ACL public COLUMN event.actor_id admin
10037; 0 0 ACL public COLUMN event.sla_type admin
10038; 0 0 ACL public COLUMN event.due admin
10039; 0 0 ACL public COLUMN event.completed admin
10040; 0 0 ACL public COLUMN event.instance_id admin
10041; 0 0 ACL public COLUMN event.pii_data admin


pg_restore -n public --use-list=<(grep -P "TABLE public event\b|ACL public (COLUMN|TABLE) event\b" $tocfile) -f - $dumpfile

--
-- PostgreSQL database dump
--
 
-- Dumped from database version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)
-- Dumped by pg_dump version 14.5 (Ubuntu 14.5-1.pgdg20.04+1)
 
SET statement_timeout = 0;
SET lock_timeout = 0;
SET idle_in_transaction_session_timeout = 0;
SET client_encoding = 'UTF8';
SET standard_conforming_strings = on;
SELECT pg_catalog.set_config('search_path', '', false);
SET check_function_bodies = false;
SET xmloption = content;
SET client_min_messages = warning;
SET row_security = off;
 
SET default_tablespace = '';
 
SET default_table_access_method = heap;

--
-- Name: event; Type: TABLE; Schema: public; Owner: admin
--

CREATE TABLE public.event (
    id text NOT NULL,
    event_notification_id text,
    type text NOT NULL,
    version text NOT NULL,
    partner_id text,
    object_id text,
    data text NOT NULL,
    reference_id1 text,
    reference_id2 text,
    reference_id3 text,
    updated timestamp with time zone DEFAULT now() NOT NULL,
    created timestamp with time zone DEFAULT now() NOT NULL,
    actor_id text,
    sla_type text,
    due timestamp with time zone,
    completed timestamp with time zone,
    instance_id text,
    pii_data json
);
 
 
ALTER TABLE public.event OWNER TO admin;
 
--
-- Name: TABLE event; Type: ACL; Schema: public; Owner: admin
--
 
GRANT SELECT,INSERT,DELETE,UPDATE ON TABLE public.event TO pii_writer;
GRANT SELECT ON TABLE public.event TO pii_reader;
GRANT SELECT,INSERT,DELETE,UPDATE ON TABLE public.event TO covereditemadm;
GRANT SELECT,INSERT,DELETE,UPDATE ON TABLE public.event TO claimhistoryadm;
 
 
--
-- PostgreSQL database dump complete
--


From: Kong Man <kong_mansatiansin@hotmail.com>
Sent: Monday, July 31, 2023 3:50 PM
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: pg_restore 14 skips ACL COLUMN when --schema is used
 
Tom,
You are right.  'Neither a TABLE nor a COLUMN ACL' are pg_restore-d, when I use -n or --schema without the TABLE toc entry.

Not knowing the behavioral change to pg_restore since PG11, I struggled to search for the root cause and made a wrong assumption based on the end result from my script.

What I do in my dbsnapshot script (to build DB baselines at each release cycle for DevOps) is (1) to pg_restore using only relevant SCHEMA toc entries, then (2) with pg_restore -n to scope out only relevant schemas it restores everything from $dumpfile.  It has been working well on PG10 for several years until we upgraded a few months ago.

Step 2 there should have included the 'public.event' table (that I showed in the previous message), because the table actually got restored with the table privileges.  I still struggle to find out why the column privileges are still missing.

Here are some simplified snippets from my script.

tocfile=/tmp/DBA-710.toc
dumpfile=/tmp/DBA-710.dump
pg_restore --list $dumpfile >$tocfile

DB=appdb
SCHEMAS=(public appschema1 appschema2)
exclusion='londiste|POLICY|PUBLICATION TABLE'
restopts=(-d "service=target dbname=$DB")

Log "[$DB]" "    restore SCHEMAs: "$(IFS='|'; cat <<<"${SCHEMAS[*]}")
pg_restore "${restopts[@]}" \
  --use-list=<(grep -A1 SCHEMA $tocfile|   # only relevant SCHEMA & ACL SCHEMA entries
               grep -E "\s("$(IFS='|'; cat <<<"${SCHEMAS[*]}")")\s") \
  $dumpfile

restopts+=($(printf " -n %s" ${SCHEMAS[@]}))  # Scope out for only relevant schemas
Log "[$DB]" "    restore data definitions"
pg_restore "${restopts[@]}" \
  --use-list=<(grep -Ev "$exclusion" $tocfile) \
  $dumpfile

Thanks,
-Kong

From: Tom Lane <tgl@sss.pgh.pa.us>
Sent: Friday, July 28, 2023 8:24 PM
To: Kong Man <kong_mansatiansin@hotmail.com>
Cc: pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: pg_restore 14 skips ACL COLUMN when --schema is used
 
Kong Man <kong_mansatiansin@hotmail.com> writes:
> pg_restore --schema in our script used to work well against pg_restore 10.  Now that we are on PostgreSQL 14.  pg_restore 14 skips ACL COLUMN, but not ACL TABLE, when --schema is used.

That's not the behavior I'm seeing.  Would you mind providing a
*complete* reproducer, not some fragments?

The behavior I'm seeing is that neither a TABLE nor a COLUMN ACL
will be restored, because (since v11) ACLs are restored only
if their table is restored, and the --use-list option you are
using excludes the table.

We could perhaps imagine special-casing that, but I think it would be
a wart, because for every other kind of object --use-list can only
filter stuff out, not filter it in.  (That is, if you are using
--use-list along with other selectivity options, an object must pass
both restrictions to be output.  I don't want to make --use-list
override other rules just for ACLs.)

It would be interesting to see your actual use-case, because
I suspect you may be doing something that there's a better way
to do now.  What set of objects are you trying to extract?

                        regards, tom lane

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
"Euler Taveira"
Дата:
On Mon, Jul 31, 2023, at 8:00 PM, Kong Man wrote:
In this example, I generate the public.event table's ToC entries for TABLE, ACL TABLE, and ACL COLUMN, then use the result on --use-list.  pg_restore generates only the CREATE TABLE and GRANTs statements at the table, but not the column, level.

You didn't provide a test case as requested but I investigated this issue
according to your description. The following commands is sufficient to produce
the analysis below.

CREATE ROLE role1;
CREATE ROLE role2;

CREATE TABLE event (
col1 text,
col2 text,
col3 text
);

GRANT SELECT ON TABLE event TO role1;
GRANT SELECT, INSERT, UPDATE, DELETE ON TABLE event TO role2;

GRANT SELECT (col1, col2) ON TABLE event TO role2;
GRANT SELECT, INSERT, UPDATE (col3) ON TABLE event TO role2;

I created these objects and ran pg_restore using a debugger.

pg_dump -Fc -f /tmp/a.dump -d test
pg_restore -l /tmp/a.dump > /tmp/a.toc
gdb --args pg_restore --use-list=/tmp/a.toc -f - /tmp/a.dump

I set a breakpoint to _tocEntryRequired function to inspect the TocEntry values.

(gdb) b _tocEntryRequired

After a few 'continue' and 'p *te' commands I got:

(gdb) c
Continuing.

Breakpoint 1, _tocEntryRequired (te=0x5555555a6910, curSection=SECTION_PRE_DATA, AH=0x5555555a05b0) at pg_backup_archiver.c:2773
2773 }
(gdb) p *te
$8 = {prev = 0x5555555a67a0, next = 0x5555555a6be0, catalogId = {tableoid = 0, oid = 0}, dumpId = 3327, section = SECTION_NONE, hadDumper = false, 
  tag = 0x555555585d30 "COLUMN event.col1", namespace = 0x5555555858b0 "public", tablespace = 0x0, tableam = 0x0, owner = 0x555555585340 "euler", desc = 0x555555585df0 "ACL", 
  defn = 0x5555555a6a00 "GRANT SELECT(col1) ON TABLE public.event TO role2;\n", dropStmt = 0x0, copyStmt = 0x0, dependencies = 0x5555555a6a40, nDeps = 2, dataDumper = 0x0, 
  dataDumperArg = 0x0, formatData = 0x555555585c70, dataLength = 0, reqs = 0, created = false, pending_prev = 0x0, pending_next = 0x0, depCount = 0, revDeps = 0x0, nRevDeps = 0, 
  lockDeps = 0x0, nLockDeps = 0}
(gdb) p te->dependencies[0]
$18 = 214
(gdb) p *AH->tocsByDumpId[214]
$17 = {prev = 0x5555555a64e0, next = 0x5555555a67a0, catalogId = {tableoid = 1259, oid = 183415}, dumpId = 214, section = SECTION_PRE_DATA, hadDumper = false, 
  tag = 0x555555584e00 "event", namespace = 0x555555584f80 "public", tablespace = 0x555555585040 "", tableam = 0x555555584380 "heap", owner = 0x555555584440 "euler", 
  desc = 0x555555584ec0 "TABLE", defn = 0x5555555a6740 "CREATE TABLE public.event (\n    col1 text,\n    col2 text,\n    col3 text\n);\n", 
  dropStmt = 0x5555555a61f0 "DROP TABLE public.event;\n", copyStmt = 0x0, dependencies = 0x0, nDeps = 0, dataDumper = 0x0, dataDumperArg = 0x0, formatData = 0x555555584d40, 
  dataLength = 0, reqs = 1, created = false, pending_prev = 0x0, pending_next = 0x0, depCount = 0, revDeps = 0x0, nRevDeps = 0, lockDeps = 0x0, nLockDeps = 0}
(gdb) p te->dependencies[1]
$21 = 3326
(gdb) p *AH->tocsByDumpId[3326]
$22 = {prev = 0x5555555a6650, next = 0x5555555a6910, catalogId = {tableoid = 0, oid = 0}, dumpId = 3326, section = SECTION_NONE, hadDumper = false, 
  tag = 0x5555555854c0 "TABLE event", namespace = 0x555555585670 "public", tablespace = 0x0, tableam = 0x0, owner = 0x555555585730 "euler", desc = 0x555555585580 "ACL", 
  defn = 0x5555555a6890 "GRANT SELECT ON TABLE public.event TO role1;\nGRANT SELECT,INSERT,DELETE,UPDATE ON TABLE public.event TO role2;\n", dropStmt = 0x0, copyStmt = 0x0, 
  dependencies = 0x5555555a6050, nDeps = 1, dataDumper = 0x0, dataDumperArg = 0x0, formatData = 0x555555585400, dataLength = 0, reqs = 1, created = false, pending_prev = 0x0, 
  pending_next = 0x0, depCount = 0, revDeps = 0x0, nRevDeps = 0, lockDeps = 0x0, nLockDeps = 0}

It means that an ACL for columns has 2 dependencies (nDeps = 2) the function
_tocEntryRequired() returns 0 (see code below).

        else if (ropt->schemaNames.head != NULL ||
                 ropt->schemaExcludeNames.head != NULL ||
                 ropt->selTypes)
        {
            /*
             * In a selective dump/restore, we want to restore these dependent
             * TOC entry types only if their parent object is being restored.
             * Without selectivity options, we let through everything in the
             * archive.  Note there may be such entries with no parent, eg
             * non-default ACLs for built-in objects.
             *
             * This code depends on the parent having been marked already,
             * which should be the case; if it isn't, perhaps due to
             * SortTocFromFile rearrangement, skipping the dependent entry
             * seems prudent anyway.
             *
             * Ideally we'd handle, eg, table CHECK constraints this way too.
             * But it's hard to tell which of their dependencies is the one to
             * consult.
             */
            if (te->nDeps != 1 || 
                TocIDRequired(AH, te->dependencies[0]) == 0)
                return 0;
        }

Hence, ProcessArchiveRestoreOptions() sets te->reqs to 0 that avoids the ACL
for columns to be restored.

te->reqs = _tocEntryRequired(te, curSection, AH);

The discussion [1] in the commit 0d4e6ed3085 does not explain if the 'if' logic
covers all cases. It certainly doesn't for the OP case. The only (hackish)
suggestion I have ATM is to detect ACL for columns and returns 1.




--
Euler Taveira

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Tom Lane
Дата:
"Euler Taveira" <euler@eulerto.com> writes:
> You didn't provide a test case as requested but I investigated this issue
> according to your description. The following commands is sufficient to produce
> the analysis below.

Thanks for looking into it!  The ingredient I missed while studying this
earlier is that the table must have *both* table-level and column-level
ACLs to provoke the issue.

> It means that an ACL for columns has 2 dependencies (nDeps = 2) the function
> _tocEntryRequired() returns 0 (see code below).

D'oh.  I think this code was correct when written, but we added an extra
dependency from column ACL to table ACL later because restoring them in
the wrong order causes problems.

> The discussion [1] in the commit 0d4e6ed3085 does not explain if the 'if' logic
> covers all cases. It certainly doesn't for the OP case. The only (hackish)
> suggestion I have ATM is to detect ACL for columns and returns 1.

Yeah, ignoring dependencies on ACLs in this logic seems like the best
way forward.  Do you want to write a patch?

            regards, tom lane



Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
"Euler Taveira"
Дата:
On Wed, Aug 2, 2023, at 5:06 PM, Tom Lane wrote:
Yeah, ignoring dependencies on ACLs in this logic seems like the best
way forward.  Do you want to write a patch?

I like your suggestion. Let me give it a try.


--
Euler Taveira

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Kong Man
Дата:
> You didn't provide a test case as requested

I apologize for not having a complete test case.  It's my first reporting a bug.  I started to get the hang of it now.

From: Euler Taveira <euler@eulerto.com>
Sent: Wednesday, August 2, 2023 4:53 PM
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Kong Man <kong_mansatiansin@hotmail.com>; pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: pg_restore 14 skips ACL COLUMN when --schema is used
 
On Wed, Aug 2, 2023, at 5:06 PM, Tom Lane wrote:
Yeah, ignoring dependencies on ACLs in this logic seems like the best
way forward.  Do you want to write a patch?

I like your suggestion. Let me give it a try.


--
Euler Taveira

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
"Euler Taveira"
Дата:
On Wed, Aug 2, 2023, at 5:53 PM, Euler Taveira wrote:
On Wed, Aug 2, 2023, at 5:06 PM, Tom Lane wrote:
Yeah, ignoring dependencies on ACLs in this logic seems like the best
way forward.  Do you want to write a patch?

I like your suggestion. Let me give it a try.

This patch should apply on all supported back branches (11-16).

In my previous email I forgot the --schema option in the pg_restore. The
correct steps are:

pg_dump -Fc -f /u/d.dump -d test
pg_restore -l /u/d.dump > /u/d.toc
pg_restore --schema=public --use-list=<(grep "ACL" /u/d.toc) -f - /u/d.dump


--
Euler Taveira

Вложения

Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Tom Lane
Дата:
"Euler Taveira" <euler@eulerto.com> writes:
> On Wed, Aug 2, 2023, at 5:53 PM, Euler Taveira wrote:
>> On Wed, Aug 2, 2023, at 5:06 PM, Tom Lane wrote:
>>> Yeah, ignoring dependencies on ACLs in this logic seems like the best
>>> way forward.  Do you want to write a patch?

>> I like your suggestion. Let me give it a try.

Hmm, changing it like that seems likely to have a lot of unexpected
side-effects.  What I had in mind was to change the 

            if (te->nDeps != 1 ||
                TocIDRequired(AH, te->dependencies[0]) == 0)
                return 0;

bit so that it would loop through the TE's dependencies to see
if any one of them is a required non-ACL TE.  We have to relax
the "te->nDeps != 1" restriction, but we still want to check
that there is a parent object that is being restored.

Some work on the associated comment block seems appropriate too.
And maybe add a test case?

            regards, tom lane



Re: pg_restore 14 skips ACL COLUMN when --schema is used

От
Tom Lane
Дата:
I wrote:
> Hmm, changing it like that seems likely to have a lot of unexpected
> side-effects.  What I had in mind was to change the 

>             if (te->nDeps != 1 ||
>                 TocIDRequired(AH, te->dependencies[0]) == 0)
>                 return 0;

> bit so that it would loop through the TE's dependencies to see
> if any one of them is a required non-ACL TE.  We have to relax
> the "te->nDeps != 1" restriction, but we still want to check
> that there is a parent object that is being restored.

I improved the patch along those lines and pushed it.

            regards, tom lane