shelve file space always increase!

[smalltalk]

>>import shelve

>>sf = shelve.open('e:/abc.db')
>>for i in range(10000):

.... sf[str(i)]=i
....

>>sf.close()
>>sf = shelve.open('e:/abc.db')
>>sf.clear()
>>sf

{}
the abc.db is always 312k though i have use clear(), how can i shrink
the space?

[skip@pobox.com]

Re: shelve file space always increase!


smalltalkthe abc.db is always 312k though i have use clear(), how can
smalltalki shrink the space?

You really can't without deleting the file. Hash file implementations trade
off file size against improve key lookup performance. Similar tradeoffs are
made in the implementation of Python's dictionary and other languages'
associative arrays.

My Google skills must be lacking this morning. Here's the best I've been
able to come up with in the way of explanation:

http://en.wikipedia.org/wiki/Associative_array#Efficient_representations

Skip

[Michael Palmer]

Re: shelve file space always increase!

On Sep 17, 6:17 am, smalltalk <ttkk1...@gmail .comwrote:

>import shelve
>sf = shelve.open('e:/abc.db')
>for i in range(10000):

>
... sf[str(i)]=i
...>>sf.close()

>sf = shelve.open('e:/abc.db')
>sf.clear()
>sf

>
{}
the abc.db is always 312k though i have use clear(), how can i shrink
the space?

shelve doesn't have any way of doing that. the only option is to read
all items from your shelve and write them to a new one.