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Can you attach Amazon EBS to multiple instances?
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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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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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Entity Framework 6 Code first Default value
...SET", and NOT the defaultValue as this defaultValue: System.DateTimeOffset.Now, will resolve to a string of the current system datetimeoffset value.
– OzBob
Apr 15 '16 at 6:53
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Hashing a dictionary?
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If your dictionary is not nested, you could make a frozenset with the dict's items and use hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representat...
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...
Are PHP include paths relative to the file or the calling code?
...g trouble understanding the ruleset regarding PHP relative include paths. If I run file A.PHP- and file A.PHP includes file B.PHP which includes file C.PHP, should the relative path to C.PHP be in relation to the location of B.PHP, or to the location of A.PHP? That is, does it matter which file ...
Why use Abstract Base Classes in Python?
...lass promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a staticly-typed language, that contract would actually be enforced by the compiler. In Pyt...
How do I get the full path of the current file's directory?
... script being run:
import os
os.path.dirname(os.path.abspath(__file__))
If you mean the current working directory:
import os
os.path.abspath(os.getcwd())
Note that before and after file is two underscores, not just one.
Also note that if you are running interactively or have loaded code from...
How to view files in binary from bash?
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sudo xxd /dev/diskn | less is now my new favorite thing.
– krs013
Jan 30 '15 at 18:39
7
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String difference in Bash
...2" > p
Greg's Bash FAQ: Working with Named Pipes
Named pipe is also known as a FIFO.
The - on its own is for standard input.
<<< is a "here string".
& is like ; but puts it in the background
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