Re: BUG #14940: Duplicated records inspite of primary key and uniqueconstraint

1.  Yes, I have used pg_dump/pg_restore.

I am sure that the ~10 problematic records were added on PG 9.6.5. and
~40  were added on  PG 9.6.6., But I do not know when they were duplicated.

2.  I have downloaded MS Win version from 
https://www.enterprisedb.com/downloads/postgres-postgresql-downloads#windows


01.12.2017 20:07, Tomas Vondra пишет:
> Hi,
>
> On 12/01/2017 04:19 PM, Сергей А. Фролов wrote:
>> The database was created at october 2016 on PG 9.5.3 then
>> backuped/restored into PG 9.6.5 and then backuped/restored into PG 9.6.6.
>>
>> I am sure that the ~10 problematic records were added on PG 9.6.5. and
>> ~40  were added on  PG 9.6.6.
>>
> By backup/restore you mean pg_dump? If that's the case, it's pretty sure
> the duplicates happened on 9.6.6 (otherwise the restore would fail).
>
> But that contradicts the 9.6.5 -> 9.6.6 upgrade, if your claim that 10
> duplicates originate on 9.6.5 is correct.
>
> BTW are you running vanilla PostgreSQL, or some of the EDB versions?
>
>> The file systems is NTFS.
>>
>> Windows 10 runs as virtual machine under Hyper-V. Windows logs contains
>> nothing suspicious on both.
>>
> No idea. My experience with modern Windows systems is minimal, but I
> suppose it certainly shouldn't corrupt data in normal operation.
>
>> I have wrote the script to generate  select to check for duplicates all
>> tables in all schemas - all other tables are OK.
>>
>> The only problem I observed - the PG dbugger hanged once and we had to
>> kill related postgres process via taskmanager (killing session had no
>> effect) , but I am shure that the killed session did not touch the
>> problem table at all.
>>
> Not sure which debugger you mean, but again - killing a process should
> not result in data corruption. It may cause the database to crash and
> perform recovery, but that's about it.
>
> regards
>