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Efficiently convert rows to columns in sql server
...onvert rows to columns in SQL server, I heard that PIVOT is not very fast, and I need to deal with lot of records.
2 Answer...
Can someone explain the traverse function in Haskell?
I am trying and failing to grok the traverse function from Data.Traversable . I am unable to see its point. Since I come from an imperative background, can someone please explain it to me in terms of an imperative loop? Pseudo-code would be much appreciated. Thanks.
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How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
Tools such as MRTG provide network throughput / bandwidth graphs for the current network utilisation on specific interfaces, such as eth0. How can I return that information at the command line on Linux/UNIX?
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Select values from XML field in SQL Server 2008
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You must use .nodes() and cross apply if xmlField contains more than one <person> elements.
– Remus Rusanu
May 22 '09 at 18:45
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jQuery .live() vs .on() method for adding a click event after loading dynamic html
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If you want the click handler to work for an element that gets loaded dynamically, then you set the event handler on a parent object (that does not get loaded dynamically) and give it a selector that matches your dynamic object like this:
$('#pare...
How to filter a dictionary according to an arbitrary condition function?
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Nowadays, in Python 2.7 and up, you can use a dict comprehension:
{k: v for k, v in points.iteritems() if v[0] < 5 and v[1] < 5}
And in Python 3:
{k: v for k, v in points.items() if v[0] < 5 and v[1] < 5}
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How to sign an android apk file
... get stuck with after you work through it, I'd suggest:
https://developer.android.com/studio/publish/app-signing.html
Okay, a small overview without reference or eclipse around, so leave some space for errors, but it works like this
Open your project in eclipse
Press right-mouse - > tools (an...
How to prevent ifelse() from turning Date objects into numeric objects
... to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
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tomcat - CATALINA_BASE and CATALINA_HOME variables
I have multiple instances of tomcat 6 running on the same server (Linux) and it works as expected. I am trying to find out what the standard practice is with regards to setting the CATALINA_HOME and CATALINA_BASE variables.
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Why use pointers? [closed]
...tionality, missing data types or for pure perfomance. More below...
When and where should I use pointers?
Short answer here is: Where you cannot use anything else. In C you don't have any support for complex datatypes such as a string. There are also no way of passing a variable "by reference" ...