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Postgres: INSERT if does not exist already
I'm using Python to write to a postgres database:
17 Answers
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How to prevent the activity from loading twice on pressing the button
I am trying to prevent the activity from loading twice if I press the button twice instantly after the first click.
19 Answ...
Why is String.chars() a stream of ints in Java 8?
...uld to be used for performance code.
However, instead of focusing on why it is done this way currently, I think this answer should focus on showing a way to do it with the API that we have gotten with Java 8.
In Java 7 I would have done it like this:
for (int i = 0; i < hello.length(); i++) {...
How to merge the current branch into another branch
... dev. I always work on dev and only check code into the master branch once it's been approved for production use. When I do so, I have to do the following:
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Determine if a String is an Integer in Java [duplicate]
I'm trying to determine if a particular item in an Array of strings is an integer or not.
9 Answers
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How to determine whether a given Linux is 32 bit or 64 bit?
When I type uname -a , it gives the following output.
21 Answers
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When is “i += x” different from “i = i + x” in Python?
...This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used for modifying mutable objects i...
How do I catch a numpy warning like it's an exception (not just for testing)?
...oject I'm doing. I'm doing a barycentric style one to avoid using an explicit for-loop as opposed to a Newton's divided difference style one. The problem I have is that I need to catch a division by zero, but Python (or maybe numpy) just makes it a warning instead of a normal exception.
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What is the tilde (~) in the enum definition?
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~ is the unary one's complement operator -- it flips the bits of its operand.
~0 = 0xFFFFFFFF = -1
in two's complement arithmetic, ~x == -x-1
the ~ operator can be found in pretty much any language that borrowed syntax from C, including Objective-C/C++/C#/Java/Java...
How to generate a Dockerfile from an image?
Is it possible to generate a Dockerfile from an image? I want to know for two reasons:
8 Answers
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