Re: [GENERAL] Results interpretation

Hi, Daniel,

On Sat, Aug 19, 2017 at 12:51 PM, Daniel Verite <daniel@manitou-mail.org> wrote:
>         Igor Korot wrote:
>
>> If I do PQexec() call, the results will be interpreted as binary or text?
>>
>> I'm trying to get an int field from the query and wonder if I need to do
>> hton() call or not?
>
> In the most general case, you may call
> PQfformat(const PGresult *res, int column_number)
> to know if a column is in text (=0) or binary format (=1)
>
> If you call PQexec("select 1") the result will be in text format.
>
> But if you'd write for instance:
>  PQexec("begin; declare c binary cursor for select 1; fetch all from c;
> end;")
> then the result would be in binary format.
>
> The point is that using PQexec() does not strictly mean that the results
> are in text, as it depends on the query itself. This might be
> significant if there's a requirement that your code has to work
> with any query.

Thank you for an explanation.
It would be nice if the documentation will explicitly state:

"The result set mode (text or binary) depends on the query being executed".

In my case I simply executing:

SELECT t.table_catalog AS catalog, t.table_schema AS schema,
t.table_name AS table, u.usename AS owner, c.oid AS table_id FROM
information_schema.tables t, pg_catalog.pg_class c, pg_catalog.pg_user
u WHERE t.table_name = c.relname AND c.relowner = usesysid AND
(t.table_type = 'BASE TABLE' OR t.table_type = 'VIEW' OR t.table_type
= 'LOCAL TEMPORARY') ORDER BY table_name;

So I presume the result set will be in a text format, right? For all columns?

Thank you.

>
>
> Best regards,
> --
> Daniel Vérité
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