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How to add column if not exists on PostgreSQL?
Question is simple. How to add column x to table y , but only when x column doesn't exist ? I found only solution here how to check if column exists.
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What is in your .vimrc? [closed]
...ed inside a .vimrc file. Typical features for a programmer would be syntax highlighting, smart indenting and so on.
72 An...
In Java, what does NaN mean?
...meters
that cause the operation to produce
some undefined result. For example,
0.0 divided by 0.0 is arithmetically undefined. Taking the square root of a
negative number is also undefined.
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how to remove untracked files in Git?
I'm working on a branch, say "experimental" branch which I branch out from my master branch.Then, I generate a user model in experimental branch, but does not add them to index yet.
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Apache Prefork vs Worker MPM
...tion at a time// here connection means single user or single request? pls explain
– user1844933
Jun 25 '19 at 7:18
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How can I add numbers in a Bash script?
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For integers:
Use arithmetic expansion: $((EXPR))
num=$((num1 + num2))
num=$(($num1 + $num2)) # Also works
num=$((num1 + 2 + 3)) # ...
num=$[num1+num2] # Old, deprecated arithmetic expression syntax
Using the external expr utili...
How to convert a color integer to a hex String in Android?
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The mask makes sure you only get RRGGBB, and the %06X gives you zero-padded hex (always 6 chars long):
String hexColor = String.format("#%06X", (0xFFFFFF & intColor));
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What is the easiest way to push an element to the beginning of the array?
...in use:
irb>> a = [ 0, 1, 2]
=> [0, 1, 2]
irb>> a.unshift('x')
=> ["x", 0, 1, 2]
irb>> a.inspect
=> "["x", 0, 1, 2]"
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Fatal error: “No Target Architecture” in Visual Studio
... try to compile my c++ project using Visual Studio 2010 in either Win32 or x64 mode I get the following error:
11 Answers
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How to install the Raspberry Pi cross compiler on my Linux host machine?
...ls.git
You wanted to use the following of the 3 ones, gcc-linaro-arm-linux-gnueabihf-raspbian, if I did not read wrong.
Go into your home directory and add:
export PATH=$PATH:$HOME/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin
to the end of the file named ~/.bashrc
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