Re: dblink get_connect_string() passes FDW option "updatable" to the connect string, connection fails.

On 11/21/2016 02:16 PM, Tom Lane wrote:
> Corey Huinker <corey(dot)huinker(at)gmail(dot)com> writes:
>> I ran into this today:
>> CREATE SERVER bob_srv FOREIGN DATA WRAPPER postgres_fdw OPTIONS ( host
>> 'localhost', dbname :'current_db' );
>> ...
>> ALTER SERVER bob_srv OPTIONS (updatable 'true');
>> SELECT *
>> FROM dblink('bob_srv','SELECT 1') as t(x integer);
>> psql:bug_example.sql:18: ERROR: could not establish connection
>> DETAIL: invalid connection option "updatable"
>
>> Is this something we want to fix?
>
> The dblink docs recommend using dblink_fdw as the FDW for this purpose,
> which would only accept legal connstr options. However, I can see the
> point of using a postgres_fdw server instead, and considering that
> dblink isn't actually enforcing use of any particular FDW type, it seems
> like the onus should be on it to be more wary of what the options are.
>
> It looks like this might be fairly easy to fix by having
> get_connect_string() use is_valid_dblink_option() to check each
> option name, and silently ignore options that are inappropriate.

Thanks for the report and analysis. I'll take a look at creating a patch
this week.

Joe

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