What are DB engine, Client server etc - HELP !!

[Viji]

Hi guys,

Sorry for my ignorance but can someone kindly explain to what exactly a DB engine is (can it exist physically??) and what a client server is? Does ADO use any of these techniques when conecting to a DB ? Also how do you compress the size of a DB and is there a technical term used to describe this ?

cheers
Viji

[phunkydude]

First of all the DBEngine is the object that drives MS Access, only one instance of it can exist per machine. As to whether it is a physical thing, well, you can set some of it's properties, and perform so of its methods, so I guess it must be a 'physical' thing.
A server is an object that serves, like a waiter, taking orders and delivering requested goods. Some machines are servers because they serve the networked machines (providing shared resources etc). Some applications are servers because they contain components that are capable of processing requests from other applications and ensuring that those request are carried out correctly. The 'correctness' of requests is usualy governed by a set of business rules ("How it must be done").
A client is like a diner, it requests things from the waiter (server) and expects to be satisfied.
Client/Server applications are made of interdependent components (client side and server side) that as a whole fulfill the requirement of the application. This can also be a physical architecture on a network, a workstation is referred to as a client and the server, a server.
The DBEngine is not directly at the disposal of ADO, by comparison to DAO. In ADO the 'server' is usually some or other DBMS, and it simplifies the complexities of communicating with the DBMS form the client.

MS Access provides functionality called compacting, which doesn't always compress the size of the DB, but will attempt to (as well as perform some other useful, behind the scenes stuff).

Now I'm no expert on the inner workings of the tehnologies, so if there's anyone out there who disagrees with my response feel free to answer, this was my attempt at answering this post.