There are features Oracle provides that have no PostgreSQL equivalent.
- Price -- it costs a lot of money. For many governmental entities, this is a huge advantage -- as they are given a budget, and they need to spend it, otherwise their budget will get reduced -- if its an excuse to spend money, based on claims of productivity, they will often deny requests to use OSS, and mandate the use of Oracle, based on its productivity-improving and more-reliable qualities that some slick salesman persuaded them of, after taking them out for steak at a 5-star restaurant somewhere, or whatever. Also; I hear plenty of government workers saying Management has a no open source software policy; for security reasons, the more money spent on the product the better, as closed source code is deemed to be more secure... For me, and business i'm involved with, this is a huge negative for Oracle, and a reason I almost always pick Postgresql; yes, Oracle delivers more, BUT in many cases you pay Oracle for every extra cent of additional incremental value Oracle delivers over Postgres, and maybe 300% more.
- RAS features -- such as clustering Oracle RAC
- Development productivity tools such as - Pro*C
- SQL Language features where Oracle's implementation is superior -- such as BLOBs. Postgres manages these poorly, for example, you cannot reliably pg_dump blobs - if your application is BLOB happy (e.g. Sharepoint-like), then Postgres is not very suitable.
- SQL Language features that have no PostgreSQL analog -- such as CONNECT BY clauses, Java class based schema and table mappings; module languages; XML types; default value funciton parameters; organize stored procedure objects using packages;