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PostgreSQL Crosstab Query
Does any one know how to create crosstab queries in PostgreSQL?
For example I have the following table:
6 Answers
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Explain Morris inorder tree traversal without using stacks or recursion
...sal. So X is made the right child of B, then current is set to Y. The tree now looks like this:
Y
/ \
A B
\
X
/ \
(Y) Z
/ \
C D
(Y) above refers to Y and all of its children, which are omitted for recursion issues. The important part is li...
Is returning by rvalue reference more efficient?
...e following
Beta_ab
Beta::toAB() const {
return Beta_ab(1, 1);
}
Now, it's properly moving a temporary Beta_ab object into the return value of the function. If the compiler can, it will avoid the move altogether, by using RVO (return value optimization). Now, you can do the following
Beta...
How to do a https request with bad certificate?
...milar but actually completely ignores the certificate check. You need to know that the certificate is valid and signed by a cert that you trust. But in common scenarios, you know that the CN won't match the hostname you connected with. For those, set ServerName on tls.Config. If tls.Config.Serve...
Remove first element from $@ in bash [duplicate]
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Exactly what I wanted. Now don't need temp variable for dereferencing first argument in "${!1}${@:2}"
– Charlie Gorichanaz
Mar 27 '17 at 22:59
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Can you attach Amazon EBS to multiple instances?
...
For anyone else who sees this answer know that Amazon has just released EFS which allows for shared auto-expanding drives that can be mounted over NFS on multiple instances.
– JoshStrange
Apr 9 '15 at 22:02
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Can I target all tags with a single selector?
I'd like to target all h tags on a page. I know you can do it this way...
10 Answers
1...
iOS app error - Can't add self as subview
I received this crash report, but I don't know how to debug it.
19 Answers
19
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How to get a complete list of object's methods and attributes?
...rns the keys in the __dict__ attribute, i.e. all the attributes accessible if the __getattr__ method is not reimplemented.
For the second question, it does not really make sense. Actually, methods are callable attributes, nothing more. You could though filter callable attributes, and, using the ins...
How can I get a list of all classes within current module in Python?
...):
for name, obj in inspect.getmembers(sys.modules[__name__]):
if inspect.isclass(obj):
print(obj)
And even better:
clsmembers = inspect.getmembers(sys.modules[__name__], inspect.isclass)
Because inspect.getmembers() takes a predicate.
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