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PostgreSQL: Can you create an index in the CREATE TABLE definition?
...e on creation. Is there are way to add them to the CREATE TABLE definition or do I have to add them afterward with another query?
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How do I find which rpm package supplies a file I'm looking for?
As an example, I am looking for a mod_files.sh file which presumably would come with the php-devel package. I guessed that yum would install the mod_files.sh file with the php-devel x86_64 5.1.6-23.2.el5_3 package, but the file appears to not to be installed on my filesystem.
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Shell - Write variable contents to a file
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Use the echo command:
var="text to append";
destdir=/some/directory/path/filename
if [ -f "$destdir" ]
then
echo "$var" > "$destdir"
fi
The if tests that $destdir represents a file.
The > appends the text after truncating the file. If you only want to append the text in $va...
How to set enum to null
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You can either use the "?" operator for a nullable type.
public Color? myColor = null;
Or use the standard practice for enums that cannot be null by having the FIRST value in the enum (aka 0) be the default value. For example in a case of color None.
pub...
How to create a generic array in Java?
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I have to ask a question in return: is your GenSet "checked" or "unchecked"?
What does that mean?
Checked: strong typing. GenSet knows explicitly what type of objects it contains (i.e. its constructor was explicitly called with a Class<E> argument, and methods will throw an exc...
What are the differences between .so and .dylib on osx?
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The Mach-O object file format used by Mac OS X for executables and libraries distinguishes between shared libraries and dynamically loaded modules. Use otool -hv some_file to see the filetype of some_file.
Mach-O shared libraries have the file type...
python requests file upload
I'm performing a simple task of uploading a file using Python requests library. I searched Stack Overflow and no one seemed to have the same problem, namely, that the file is not received by the server:
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What's the shortest code to cause a stack overflow? [closed]
To commemorate the public launch of Stack Overflow, what's the shortest code to cause a stack overflow? Any language welcome.
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Count number of objects in list [closed]
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length(x)
Get or set the length of vectors (including lists) and factors, and of any other R object for which a method has been defined.
lengths(x)
Get the length of each element of a list or atomic vector (is.atomic) as an integer o...
c++ boost::multi_index composite keys efficiency - c++1y / stl - 清泛IT社区，为创新赋能！
...container stuff and have a rather in-depth question that hopefully a boost or C++ container expert might know (my knowledge in C++ containers is pretty basic). For reference, the boost documentation on composite keys can be found here: boost::multi_index composite keys.When using a composite key, th...