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What is the dual table in Oracle?
I've heard people referring to this table and was not sure what it was about.
14 Answers
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Appending a line to a file only if it does not already exist
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Just keep it simple :)
grep + echo should suffice:
grep -qxF 'include "/configs/projectname.conf"' foo.bar || echo 'include "/configs/projectname.conf"' >> foo.bar
-q be quiet
-x match the whole line
-F pattern is a plain st...
Getting the location from an IP address [duplicate]
I want to retrieve information like the city, state, and country of a visitor from their IP address, so that I can customize my web page according to their location. Is there a good and reliable way to do this in PHP? I am using JavaScript for client-side scripting, PHP for server-side scripting, an...
Swift - How to convert String to Double
I'm trying to write a BMI program in swift language.
And I got this problem: how to convert a String to a Double?
29 Answer...
How can I initialize an ArrayList with all zeroes in Java?
It looks like arraylist is not doing its job for presizing:
5 Answers
5
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Correct Bash and shell script variable capitalization
I run across many shell scripts with variables in all caps, and I've always thought that there is a severe misunderstanding with that. My understanding is that, by convention (and perhaps by necessity long ago), environment variables are in all-caps.
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How can I create a keystore?
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To answer the question in the title, you create a keystore with the Java Keytool utility that comes with any standard JDK distribution and can be located at %JAVA_HOME%\bin. On Windows this would usually be C:\Program Files\Java\jre7\bin.
So on Windows, op...
How to remove a key from Hash and get the remaining hash in Ruby/Rails?
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Rails has an except/except! method that returns the hash with those keys removed. If you're already using Rails, there's no sense in creating your own version of this.
class Hash
# Returns a hash that includes everything but the given keys.
# hash = { a: true, b: false, c: n...
What is pip's equivalent of `npm install package --save-dev`?
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There isn't an equivalent with pip.
Best way is to pip install package && pip freeze > requirements.txt
You can see all the available options on their documentation page.
If it really bothers you, it wouldn't be too difficult to write a ...
Defining an abstract class without any abstract methods
Can I define an abstract class without adding an abstract method?
12 Answers
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