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In which case do you use the JPA @JoinTable annotation?
... database, the hibernate is selecting with the left outer join and I dont know why..
– MaikoID
Dec 12 '12 at 20:49
2
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How do I detect unsigned integer multiply overflow?
...
I see you're using unsigned integers. By definition, in C (I don't know about C++), unsigned arithmetic does not overflow ... so, at least for C, your point is moot :)
With signed integers, once there has been overflow, undefined behaviour (UB) has occurred and your program can do anything (...
String concatenation vs. string substitution in Python
... large boosts in performance..."
If performance matters, this is good to know.
However, performance problems I've seen have never come down to string operations. I've generally gotten in trouble with I/O, sorting and O(n2) operations being the bottlenecks.
Until string operations are the perfor...
Python nonlocal statement
...: 2
# outer: 1
# global: 0
To this, using nonlocal, where inner()'s x is now also outer()'s x:
x = 0
def outer():
x = 1
def inner():
nonlocal x
x = 2
print("inner:", x)
inner()
print("outer:", x)
outer()
print("global:", x)
# inner: 2
# outer: 2
# global...
Relationship between SciPy and NumPy
...ion. Why scipy is preferring the library function over the ufunc, I don't know off the top of my head.
EDIT: In fact, I can answer the log10 question. Looking in the scipy __init__ method I see this:
# Import numpy symbols to scipy name space
import numpy as _num
from numpy import oldnumeric
fro...
Best way to store date/time in mongodb
... @Thilo: MongoDB has no special 'datetime' object as far as I know. It uses the JavaScript Date type, which is stored in BSON form.
– Niels van der Rest
Sep 24 '10 at 8:04
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How to determine SSL cert expiration date from a PEM encoded certificate?
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If you just want to know whether the certificate has expired (or will do so within the next N seconds), the -checkend <seconds> option to openssl x509 will tell you:
if openssl x509 -checkend 86400 -noout -in file.pem
then
echo "Certific...
Read entire file in Scala?
... I'm too late to the party, but I'd hate for people not to know they can do "io.File("/etc/passwd").slurp" in trunk.
– psp
Aug 26 '09 at 3:48
28
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How to install therubyracer gem on 10.10 Yosemite?
... Thank's, it work for me, just for copy/paste guy like me, we are now at gem install pkg/libv8-3.16.14.7-x86_64-darwin-14.gem
– Christophe Dufour
Oct 21 '14 at 9:58
2
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Can I use a binary literal in C or C++?
...'ve seen a number of embedded-systems compilers that support it. I don't know any particular reason it shouldn't be a standard language feature.
– supercat
Aug 1 '11 at 21:34
5
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