Re: Reducing some DDL Locks to ShareLock

Simon Riggs wrote:
>
> My main focus is on these commands
> * CREATE TRIGGER
> * ALTER TABLE ..  ADD PRIMARY KEY
> * ALTER TABLE ..  ADD FOREIGN KEY
>
> because those are the most painful ones. We could make it work against
> more, but we'd need to rewrite lots and lots of catalog update code.
>
>
>   

Anything that scans the table is a prime candidate. In particular, for 
parallel pg_dump, ALTER TABLE ... ADD UNIQUE is important, as well as 
possibly other table constraints.

cheers

andrew