Snapshot Materialized Views - GSoC

First of all, I really appreciate you gave me change to participate on
GSoC. It's great chance for me.

For this summer I have plan to make patch inplementing snapshot
materialized views (MV). I believe it will not be end of effort to
implement more of MV. But I / we need discuss MV syntax and exact
behaviour so I have some questions about that for all of you:

a) relkind for materialized view in pg_class?
- I'm voting for char 'm' quite obvious why, but not sure about alias:
1 - RELKIND_MVIEW
2 - RELKIND_MATVIEW
or any other ideas?

b) create MV syntax?
- CREATE MATERIALIZED VIEW mvname AS ..., I think it is quite
obvious to do so, but I had to ask

c) refresh command syntax?
1 - ALTER MATERIALIZED VIEW mvname REFRESH
or
2 - REFRESH MATERIALIZED VIEW mvname

d) what to do when someone use INSERT, UPDATE or DELETE against MV?
1 - raise error? - I prefer this option
2 - let commands change MV? (no chance to let changes propagate to
source tables, not for this summer :)
if pg lets user to DML against MV, I expect that triggers should
work too

e) what to do when someone drop table or column?
- it behave like it was a classic view. Fire error and hint
- CASCADE option will remove MV

ERROR: cannot drop table adresa because other objects depend on it
DETAIL: materialized view adresa_mv depends on table adresa
HINT: Use DROP ... CASCADE to drop the dependent objects too.