Store hashes of objects in BTrees instead of objects?

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Hello,
The BTrees documentation 
<https://btrees.readthedocs.io/en/latest/overview.html#related-data-structures> 
tells us that :

*There are variants of the data structures specialized to numbers, which 
are faster and more memory efficient than those dealing with objects.*

Also Jason Madden did some benchmarking 
<https://github.com/zopefoundation/BTrees/issues/100#issuecomment-518201210> 
to illustrate this.

I just realized that, at least on my system, python hashes are less than 
64bits long so they can fit as LOBTree keys.

>>> from BTrees.LOBTree import LOBTree
>>> h = hash("whatever")
>>> h.bit_length()
63

>>> t = LOBTree()
>>> t[h] = "anything"
>>> t[h]
'anything'

I was wondering if there are drawbacks to systematically using hashes of 
strings as LOBTree keys, instead of those whole strings as OOBTree keys. 

What do you think?


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<div>Hello,</div><div>The <a href=3D"https://btrees.readthedocs.io/en/lates=
t/overview.html#related-data-structures">BTrees documentation</a> tells us =
that :<br></div><div><br></div><div><i>There are variants of the data struc=
tures specialized to
numbers, which are faster and more memory efficient than those dealing
with objects.</i></div><div><br></div><div>Also Jason Madden <a href=3D"htt=
ps://github.com/zopefoundation/BTrees/issues/100#issuecomment-518201210">di=
d some benchmarking</a> to illustrate this.</div><div><br></div><div>I just=
 realized that, at least on my system, python hashes are less than 64bits l=
ong so they can fit as LOBTree keys.</div><div><br></div><div>&gt;&gt;&gt; =
from BTrees.LOBTree import LOBTree<br>&gt;&gt;&gt; h =3D hash("whatever")<b=
r>&gt;&gt;&gt; h.bit_length()<br>63<br><br>&gt;&gt;&gt; t =3D LOBTree()<br>=
&gt;&gt;&gt; t[h] =3D "anything"</div><div>&gt;&gt;&gt; t[h]</div><div>'any=
thing'</div><div><br></div><div>I was wondering if there are drawbacks to s=
ystematically using hashes of strings as LOBTree keys, instead of those who=
le strings as OOBTree keys. <br></div><div><br></div><div>What do you think=
?<br></div><div><br></div><div><br></div>

<p></p>

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