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Is there any performance gain in indexing a boolean field?
I'm just about to write a query that includes a WHERE isok=1 . As the name implies, isok is a boolean field (actually a TINYINT(1) UNSIGNED that is set to 0 or 1 as needed).
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How do I generate random number for each row in a TSQL Select?
I need a different random number for each row in my table. The following seemingly obvious code uses the same random value for each row.
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What is the difference between FragmentPagerAdapter and FragmentStatePagerAdapter?
What is the difference between FragmentPagerAdapter and FragmentStatePagerAdapter ?
7 Answers
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How can I export the schema of a database in PostgreSQL?
My computer broke down but fortunately I backed up
the folder C:\Program Files\PostgreSQL.
8 Answers
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Best way to encode text data for XML in Java?
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Very simply: use an XML library. That way it will actually be right instead of requiring detailed knowledge of bits of the XML spec.
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How can I determine whether a Java class is abstract by reflection
...rating through classes in a Jar file and wish to find those which are not abstract. I can solve this by instantiating the classes and trapping InstantiationException but that has a performance hit as some classes have heavy startup. I can't find anything obviously like isAbstract() in the Class.java...
static function in C
...foo); /* ok, f2 is in the same translation unit */
/* (basically same .c file) as f1 */
}
int f2(int foo) {
return 42 + foo;
}
main.c:
int f1(int); /* prototype */
int f2(int); /* prototype */
int main(void) {
f1(10); /* ok, f1 is visible to the linker */
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Pull remote branch into local repo with different name?
Alright I did a little bit of research on this but I couldn't find an exact answer, so I have to ask.
2 Answers
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Google Maps v3 - limit viewable area and zoom level
is it possible to limit Google map v3 to a certain area? I want to allow displaying only some area (e.g. a country) and disallow the user to slide elsewhere. Also I want to restrict the zoom level - e.g. only between levels 6 and 9. And I want to use all the base map types.
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How do I kill background processes / jobs when my shell script exits?
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To clean up some mess, trap can be used. It can provide a list of stuff executed when a specific signal arrives:
trap "echo hello" SIGINT
but can also be used to execute something if the shell exits:
trap "killall background" EXIT
It's a builtin, so h...