Re: how does postgresql work - Mailing list pgsql-novice

Jennifer,

well, there's these tubes, see... 

i'm just making fun of a USA Congressman who called the internet a series of tubes that get clogged up like water pipes. ;-)

PGSQL is a database software application.  As such, PGSQL has what is called an API.  i think this stands for application programmer's interface.

in other words, unless i'm butchering the intent of the term API, PGSQL has a certain interface that an application programmer can interact with.

to draw an analogy, a gas pedal is one "interface" to your car's engine.  you don't need to know how the engine works to accelerate your car due its simple "driver's interface."

PGSQL is similar.  it has an interface that waits for the application to send it data in a certain format.  when it receives this information in the proper format, it responds as it is programmed to respond.

usually, PGSQL is mated up with an application programming language.  I use PHP.  I'm learning ruby.  Others use java, python, .NET...  and the list goes on and on and on.

if that wasn't complicated enough, developers have created database abstraction layers.  i use adodb and like it a lot.  the abstraction layer, in theory, is designed to allow the programmer to interface with the abstraction layer which, in turn, interacts with the database API.

this is nice b/c databases sometimes change or someone is developing for two different databases with two different APIs.  using adodb, my calls to each of the two databases will be the same and the abstraction layer will send the appropriate code to the appropriate database..

in practice, the databases have enough proprietary functionality that significant work is often required if one wants to change the underlying database.

best,

oe1