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String literals and escape characters in postgresql
...s such:
insert into EscapeTest (text) values (E'This is the first part \n And this is the second');
This suppressed the warning, but the text was still not being returned correctly. When I added the additional slash as Michael suggested, it worked.
As such:
insert into EscapeTest (text) values ...
Why are we not to throw these exceptions?
...
Exception is the base type for all exceptions, and as such terribly unspecific. You shouldn’t ever throw this exception because it simply does not contain any useful information. Calling code catching for exceptions couldn’t disambiguate the intentionally thrown excep...
Why does Convert.ToString(null) return a different value if you cast null?
...e to any reference type. In this case string is more specific than object and hence it will be picked as the winner.
In the null as object you've solidified the type of the expression as object. This means it's no longer compatible with the string overload and the compiler picks the object over...
How to generate an openSSL key using a passphrase from the command line?
...irst - what happens if I don't give a passphrase? Is some sort of pseudo random phrase used? I'm just looking for something "good enough" to keep casual hackers at bay.
...
Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application
...me here because I wanted to know whether adb install -r would remove first and then install or upgrade my app. Although adb's description is not very clear (-r: replace existing application), adb install -r does indeed upgrade your app and does not remove your app data. Therefore suitable to test up...
C# version of java's synchronized keyword?
...: only apply thread-safety when you know you actually are going to use it (and test it).
For the method-level stuff, there is [MethodImpl]:
[MethodImpl(MethodImplOptions.Synchronized)]
public void SomeMethod() {/* code */}
This can also be used on accessors (properties and events):
private int ...
How do I build a numpy array from a generator?
...ping this in mind, it is technically impossible to take a generator object and turn it into an array unless you either:
can predict how many elements it will yield when run:
my_array = numpy.empty(predict_length())
for i, el in enumerate(gimme()): my_array[i] = el
are willing to store its elemen...
Why is XOR the default way to combine hashes?
Say you have two hashes H(A) and H(B) and you want to combine them. I've read that a good way to combine two hashes is to XOR them, e.g. XOR( H(A), H(B) ) .
...
Assigning a variable NaN in python without numpy
...r all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation on NaN value may cause subtle issues when trying to store NaN inside con...
What's the best online payment processing solution? [closed]
...rovide name here'" type answer because like so many things it is a balance and the reasons for choosing a payment processing solution tend to be complex.
Volume / Value
The most important factor in choosing a secure payment clearance service (the people who will connect to the banking networks and c...