Your first question may be "How do I pronounce this darn thing?" It's simple—in four syllables, like this: Post - gress - cue - ell. With that out of the way, we can get down to business. According to Bruce Momjian, PostgreSQL is currently the "most advanced open source relational database management system." Let's break this statement down and see just what he means.
- Most Advanced. This term doesn't necessarily mean fastest, or most widespread, although the use of PostgreSQL is increasing. PostgreSQL is "most advanced" in that it supports the most features and is closest to SQL92 compliance. Apart from the software level, PostgreSQL has an extremely talented and mature core of developers who keep this a top-notch piece of software.
- Open Source. This term has evolved from relative obscurity to a market buzzword in a very short period of time. As you probably already know, Open Source means that the source code is available to anyone for no cost—in effect, allowing anyone to help with the project's development. More specifically, PostgreSQL is maintained under the BSD License. This is as open as open gets.
- Relational Database Management System. Put simply, this
is a system that allows the manipulation of data according to the
rules of relational algebra. Data is stored in tables of columns (attributes)
and rows (tuples). Through the use of keys, these tables can relate
to one other. A true RDBMS must support ACID, which stands for:
A—Atomicity. Perhaps better known as transactions. This is where a series of queries can execute as one query. If one query fails, all related ones take place.
C—Consistency of Preservation. A database has consistency of preservation if the database is taken from one legal state to another.
I—Isolation. When a transaction is being executed, other transactions should not interfere whatsoever.
D—Durability or permanency. Changes applied to the database must be committed and must survive failure.
This is all well and good, but probably means very little until you get the software installed and running, and that's what you came here for, right?