Fixes#679
This change sets the default commit protocol for distributed DDL
commands to '1pc'. If the user issues a distributed DDL command with
this default setting, then once in a session, a NOTICE message is
shown about using '2pc' being extra safe.
- Enables using VOLATILE functions (like nextval()) in INSERT queries
- Enables using STABLE functions (like now()) targetLists and joinTrees
UPDATE and INSERT can now contain non-immutable functions. INSERT can contain any kind of
expression, while UPDATE can contain any STABLE function, so long as a Var is not passed
into the STABLE function, even indirectly. UPDATE TagetEntry's can now also include Vars.
There's an exception, CASE/COALESCE statements may not contain mutable functions.
Functions calls in master_modify_multiple_shards are also evaluated.
Eren Başak
Brian Cloutier