data structures versus data bases???
johnroth at ameritech.net
Mon Nov 12 17:57:04 CET 2001
"husam" <husalwan at sci.kun.nl> wrote in message
news:3BEFD59B.9000709 at sci.kun.nl...
> John Roth wrote:
> > "husam" <husalwan at sci.kun.nl> wrote in message
> > news:3BED54C2.1010608 at sci.kun.nl...
> >>yes, i understand the general defenition of data bases and of data
> >>structures. i should in fact put the question like this:
> >>is a given dictionary or list of a set of data, a data base?
> > In some respect, it depends on your point of view. All of the
> > data structures quoted in the previous articles in the thread
> > are in fact collections with different access policies. Data bases
> > are also collections with different access policies (SQL being
> > by far the most popular one).
> > I normally think of a data structure as an abstract description
> > of a way to organize a collection, a collection as a concrete
> > example of a data structure with specific data that is in
> > memory, and a data base as something that is managed
> > by an external piece of software, called a 'data base
> > manager.'
> > John Roth
> ok, the thing that i can make up from this discussion is that the
> difference between data base and data structures (list, dicts and
> tuples) lies in the usage policy. i mean data access and data
> manipulation methods differe, but they might resemble each other by
> way data is organized. to be more specific, i have builed a small
> application to manage my audio cds. i made two programs in the first
> i stored the cds and programs in lists. the length of main_list
> represent cd numbers, and each cd number is a list of the names of the
> audio tracks in that cd. in this program i can manipulate the items in
> any way i desire. in the second program i organized the cds and the
> audio tracks in dictionaries. to go back to the subject and according
> what i understood i can now call my application is a data base
> or my cds are organized in a data base! right?
Since there're out there on a permanent file, that's technically
correct. The formal notion of a data base requires that other programs
be able to get at the data with 'relative' ease, which is why most
people don't really regard a flat file as a data base.
More information about the Python-list