Re: Server postgres_fdw "fetch_size" option cannot be updated

On Thu, Dec 28, 2017, at 15:42, Jeff Janes wrote:
> On Thu, Dec 28, 2017 at 12:33 PM, Logan Owen <pgsql@s1devops.com> wrote:
>> Hi everyone,
>>
>>  I'm playing around with postgres_fdw (version 1.0), and ran into an issue where I wanted to update the "fetch_size"
optionon the server level: 
>>
>>  sql> CREATE SERVER test_remote FOREIGN DATA WRAPPER postgres_fdw OPTIONS (host 'postgres2', dbname 'test',
updatable'false') 
>>  [2017-12-28 10:30:13] completed in 35ms
>>  sql> ALTER SERVER test_remote OPTIONS (set fetch_size '50')
>>  [2017-12-28 10:30:26] [42704] ERROR: option "fetch_size" not found
>>
>>  However, I am able to properly set the "fetch_size" when originally defining the server:
>>
>>  sql> CREATE SERVER test_remote2 FOREIGN DATA WRAPPER postgres_fdw OPTIONS (host 'postgres2', dbname 'test',
updatable'false', fetch_size '50') 
>>  [2017-12-28 10:31:26] completed in 24ms
>>
>  
> You use 'set' only if a value already exists and you wish to change it.  Since no value exists (the default does not
count),you just do 
>
> ALTER SERVER test_remote OPTIONS (fetch_size '50');
>
> Yes, this is confusing.  But it is also documented, and I think it is required by the SQL/MED standard.
>
> Cheers,
>
> Jeff

Hi Jeff,

Thank you for quick reply, and you are right, it is referenced in the documentation for ALTER SERVER
(https://www.postgresql.org/docs/9.6/static/sql-alterserver.html):

> Change options for the server. ADD, SET, and DROP specify the action to be performed. ADD is assumed if no operation
isexplicitly specified. Option names must be unique; names and values are also validated using the server's
foreign-datawrapper library. 

My apologies for not being more thorough before assuming an issue, and have a great day!
Logan