Re: [WIP] Special role for subscriptions

Hello!
I started work on patch (draft attached). Draft has changes related only to `CREATE SUBSCRIPTION`. 
I also introduce a new status (DEFFERED)  for tables in `FOR TABLE` clause (but not in publication).
New column in pg_subscription (suballtables) will be used in `REFRESH` clause

09.11.2018, 15:24, "Evgeniy Efimkin" <efimkin@yandex-team.ru>:
> Hi!
> In order to support create subscription from non-superuser, we need to make it possible to choose tables on the
subscriberside:
 
>     1. add `FOR TABLE` clause in `CREATE SUBSCRIPTION`:
>        ```
>         CREATE SUBSCRIPTION subscription_name
>             CONNECTION 'conninfo'
>             PUBLICATION publication_name [, ...]
>             [ FOR TABLE [ ONLY ] table_name [ * ] [, ...]| FOR ALL TABLES ]
>             [ WITH ( subscription_parameter [= value] [, ... ] ) ]
>        ```
>        ... where `FOR ALL TABLES` is only allowed for superuser.
>        and table list in `FOR TABLES` clause will be stored in pg_subscription_rel table (maybe another place?)
>
>     2. Each subscription should have "all tables" attribute.
>        For example via a new column in pg_subscription "suballtables".
>
>     3. Add `ALTER SUBSCRIPTION (ADD TABLE | DROP TABLE)`:
>        ```
>         ALTER SUBSCRIPTION subscription_name ADD TABLE [ ONLY ] table_name [WITH copy_data];
>         ALTER SUBSCRIPTION subscription_name DROP TABLE [ ONLY ] table_name;
>        ```
>     4. On `ALTER SUBSCRIPTION <name> REFRESH PUBLICATION` should check if table owner equals subscription owner. The
checkis ommited if subscription owner is superuser.
 
>     5. If superuser calls `ALTER SUBSCRIPTION REFRESH PUBLICATION` on subscription with table list and non-superuser
owner,we should filter tables which owner is not subscription's owner or maybe we need to raise error?
 
>
> What do you think about it? Any objections?
>
> 07.11.2018, 00:52, "Stephen Frost" <sfrost@snowman.net>:
>>  Greetings,
>>
>>  * Evgeniy Efimkin (efimkin@yandex-team.ru) wrote:
>>>   As a first step I suggest we allow CREATE SUBSCRIPTION for table owner only.
>>
>>  That's a nice idea but seems like we would want to have a way to filter
>>  what tables a subscription follows then..? Just failing if the
>>  publication publishes tables that we don't have access to or are not the
>>  owner of seems like a poor solution..
>>
>>  Thanks!
>>
>>  Stephen
>
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> Ефимкин Евгений

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Ефимкин Евгений