[fubarred]

Streaming: it really depends on the scale of use-case: denormalized datawarehousing vs. financial tranasctions vs. MMORPG user state vs. etc. For some apps, a subscribe / notify pattern for responding to streams of messages (a-la MQTT) might be more workable.

An explanation of Postgres / Oracle similarities:

Postgres Plus AS (the commercial product) aims to be a drop-in replacement for Oracle, so it's no surprise that Postgres tends to overlap with regard to Oracle functionality. It also makes it safer to choose Postgres as a default starting point, because the migration options to Oracle / Postgres Plus / etc. are there.

http://www.enterprisedb.com/products-services-training/produ...

Disclaimer: unaffiliated pimping Postgres Plus because it likely subsidizes Postgres OSS dev. (Postgres OSS code is generally well-engineered.)