On Wed, 8 Aug 2007, TheSarge wrote:
> I have five data files, that are used to build a database.
>
> 1.txt
> 2.txt
> 3.txt
> 4.text
> 5.txt
>
> I want to build a database using a persistent dictionary (shelve).
>
> The specifications are that the key for each dictionary keyword pair, is the
> lefthand side
> value of the # sign, and the corresponding value for the data is the phrase
> on the
> righthand side.
>
> Can someone help me manipulate this please? I can't not get a grasp on
> shelves and on what I need to do.
Basically, once you create a shelf object (which you do by calling
shelve.open on a new or existing filename), you treat it like a
dictionary. When you close it, the values in the dictionary are saved.
For example, in one program, you would have:
shelf = shelve.open("testfile.shelf")
And later, lines like:
shelf["a"] = "Alligators all around" # just like a dictionary.
shelf["b"] = "Bursting balloons"
. . .
shelf["z"] = "Zippety Zound"
and eventually:
shelf.close()
Then, in another program (or later in the same program) you could re-open
the shelf-file and use it as a dictionary
shlf = shelv.open("testfile.shelf")
for key in shlf:
print key, shlf[key]
and you should see, in arbitrary order, things like:
b Bursting balloons
r Riding reindeer
e Entertaining Elephants
a Aligators all around
Is this a homework problem, or a real-life application?
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