Re: pg_dump with disable trigger

On Wed, Apr 11, 2018 at 6:46 AM, David G. Johnston <
david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

> On Tue, Apr 10, 2018 at 4:17 PM, Soni M <diptatapa(at)gmail(dot)com> wrote:
>
>> Hello All,
>>
>> I think I found bug on pg_dump 9.6.8.
>> The bug arise when using pg_dump with --disable-trigger option.
>> The command just :
>> pg_dump -f /tmp/test_disable_trigger.sql -a -b --disable-triggers -t
>> some_table some_database
>> On the resulted script, it simply did
>>
>> ALTER TABLE public.some_table DISABLE TRIGGER ALL;
>> COPY command
>> ALTER TABLE public.some_table ENABLE TRIGGER ALL;
>>
>> This become a problem, when the destination table already has Disabled
>> user triggers, it gets enabled by the dump script.
>>
>
> I would classify this as a limitation of the concept as opposed to a
> bug.​ I was going to say a bit more but I'm not that fluent with disabled
> triggers mode in dump/restore setups. I would advise using pg_restore and
> leaving the disable triggers option of the pg_dump command. It lacks
> sufficient information to write an appropriate script for an unknown target
> server.
>
> If you have issues with pg_restore those would be more easily be deemed as
> bugs.
>
> FWIW we have a "SET LOCAL" command that results in GUC variables being
> restored to their state post-transaction; we'd need a similar command for
> pg_dump to work properly.
>
> It also altered another kind of trigger like Triggers firing on replica
>> only, get altered to ordinary triggers.
>>
>
> ​This seems like a bug - though I'm not going to be confirming the
> behavior and you haven't provided evidence.
> ​
>
This happen when copying slony log table.

Before restore :

Table
"_consprod_replication.sl_log_1"
Indexes:
"PartInd_consprod_replication_sl_log_1-node-2" btree (log_txid) WHERE
log_origin = 2
"sl_log_1_idx1" btree (log_origin, log_txid, log_actionseq)
Triggers firing on replica only:
apply_trigger BEFORE INSERT ON _consprod_replication.sl_log_1 FOR EACH
ROW EXECUTE PROCEDURE
_consprod_replication.logapply('_consprod_replication')

And after restore :
Table
"_consprod_replication.sl_log_1"
Indexes:
"PartInd_consprod_replication_sl_log_1-node-2" btree (log_txid) WHERE
log_origin = 2
"sl_log_1_idx1" btree (log_origin, log_txid, log_actionseq)
Triggers:
apply_trigger BEFORE INSERT ON _consprod_replication.sl_log_1 FOR EACH
ROW EXECUTE PROCEDURE
_consprod_replication.logapply('_consprod_replication')

> David J.
>
>

--
Regards,

Soni Maula Harriz