Re: libpq and mysterious "invalid byte sequence for encoding UTF8".

On 01.02.2021 15:55, Tom Lane wrote:
> =?UTF-8?B?SmnFmcOtIFBhdmxvdnNrw70=?= <jiri(at)pavlovsky(dot)eu> writes:
>>     Jan 26 08:40:57 ip-172-16-10-94 postgres[11334]: [113-1] 2021-01-26
>> 09:40:57.505 CET [11334] jira(at)project-syndicate LOG:  execute <unnamed>:
>>
>>         UPDATE contacts SET Pos = $1::varchar, Title = $2::varchar,
>> PaperID = $3::int, FirstName = $4::varchar, LastName = $5::varchar, Func
>> = $6::varchar, Tel1 = $7::text, Fax1 = $8::text, Email1 = $9::varchar,
>> Tel2 = $10::text, Fax2 = $11::text, Email2 = $12::varchar, MainContact =
>> $13::boolean, PublDataContact = $14::boolean, InvContact = $15::boolean
>> WHERE ContactID = $16::int
>>         Jan 26 08:40:57 ip-172-16-10-94 postgres[11334]: [113-2]
>> 2021-01-26 09:40:57.505 CET [11334] jira(at)project-syndicate DETAIL:
>> parameters: $1 = NULL, $2 = NULL, $3 = '1702', $4 = NULL, $5 = NULL, $6
>> = NULL, $7 = NULL, $8 = NULL, $9 = NULL, $10 = NULL, $11 = NULL, $12 =
>> NULL, $13 = NULL, $14 =  NULL, $15 = NULL, $16 = '14340'
>>         Jan 26 08:40:57 ip-172-16-10-94 postgres[11334]: [114-1]
>> 2021-01-26 09:40:57.544 CET [11334] jira(at)project-syndicate ERROR:
>> invalid byte sequence for encoding "UTF8": 0x80
> This log entry shows that your query text and parameters all made it to
> the backend just fine. So I don't think your issue is on the client side.
> I'm wondering if the error could be from (say) triggers doing fancy data
> manipulations. Noting your use of ON UPDATE CASCADE, it'd be worth
> checking indirectly-affected tables as well.
>
> regards, tom lane

Thanks for the answer.

I don't think triggers or constraints are the issue.

The exact same code works if I create a small test program with the same
query and the same parameters.

But when used in the context of the whole application it gives the error.

 I don't know what should I try. I tried all possible combinations of
parameters.

I have just even tried to disable triggers and remove any constraints
from the table. Same error.