747b0392__5_1___Postgres_OnLine_Journal__Microsoft_SQL_Server_2008
[Feature] Materialized/Indexable Views [MySQL 5.1] No [PostgreSQL 8.4] No, but there are I think 2 contrib modules e.g. matviews that are simple and basically rebuild the materialized view [Microsoft SQL Server 2008] 
Yes but varies slightly depending on if you are running SQL Express, Workgroup, Standard, Enterprise and numerous restrictions on your views that makes it of limited use