Re: FDW-based dblink (WIP)

Peter Eisentraut <peter_e@gmx.net> wrote:

> This patch is listed in the commitfest, but I think the consensus was
> that it needed some rework.

No doubt, but SQL/MED will require a lot of works. Can we split the work
into small parts? I intended FDW-based dblink to be one of the split jobs.

Here are some random considerations:
 * Split dblink to connector and connection management layers.   Present dblink has own name-based connection
managementand error   handling routines, but I think we should share them amoung connectors.
 
 * CREATE FOREIGN TABLE supports only select query in SQL standard.   I thnk we will still need to have free-style SQL
executorlike dblink   even when we support SQL/MED It is not a waste to include dblink in core.
 
 * Consider interface of extensible connecter to be able to connect   other DBMSs. Especially, there are many
differencesin usage of 2PC.
 
 * Automatic 2PC is very useful if we supports non-select query in SQL/MED.   It would be better to have some
infrastructurefor it.
 

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center