Re: BDR truncate and replication sets

Sylvain MARECHAL wrote:
> Hello all,
>
> To avoid replication of some tables, I use a specific replication set.
> For example, with 2 nodes 'node1' and 'node2' and a table 'test' which
> content shall not be replicated, I do the following:
>
> mydb=# CREATE TABLE test (i INT PRIMARY KEY NOT NULL);
> mydb=# SELECT bdr.table_set_replication_sets('test', ARRAY['test_rep_set']);
>
> After that, adding (INSERT) or removing (DELETE) data in 'node1' or 'node2'
> can be done independently.
> The exception is with TRUNCATE: In case it is called, data is removed on
> both nodes.
>
> Is it a feature or a bug?

I think it's an oversight. Replication sets were added later than the
TRUNCATE trigger, so the design for the latter does not consider the
former as far as I know.

> (I am not sure it is related with
> https://github.com/2ndQuadrant/bdr/issues/93)

Doesn't look related.

> Is there a workaround?
> (deleting the truncate trigger seems to work, but I am sure it is safe to do
> it)

Well, the truncate trigger is there to replicate the truncate to other
servers. If you don't want truncate to be propagated, dropping the
trigger is one way to achieve that effect.

--
Álvaro Herrera http://www.2ndQuadrant.com/
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