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Spring @Transactional - isolation, propagation
...ion. I think if you understand the dirty reads concept you will be able to select a good option.
Example of when a dirty read can occur:
thread 1 thread 2
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write(x) |
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rollback |
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What is the difference between Serializable and Externalizable in Java?
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We used Externalizable for large collections of "selected IDs" -- it was far more efficient externalizing as more-or-less a count & an array of primitive ints, than default serialization. That's a very simple usecase, nothing "special" or "unique".
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Sanitizing strings to make them URL and filename safe?
...OU
echo normal_chars('üÿÄËÏÖÜŸåÅ'); // uyAEIOUYaA
Based on the selected answer in this thread: URL Friendly Username in PHP?
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Android: alternate layout xml for landscape mode
...clicking on the button in the visual editor shown in the screenshot below. Select "Create Landscape Variation"
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What is stability in sorting algorithms and why is it important?
...Sort
Gnome Sort
Odd–even Sort
Unstable Sorting Algorithms:
Heap sort
Selection sort
Shell sort
Quick sort
Introsort (subject to Quicksort)
Tree sort
Cycle sort
Smoothsort
Tournament sort(subject to Hesapsort)
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PHP memory profiling
...01-29) which can be used in Qcachegrind or similar tool. Just make sure to select the memory option :)
From the docs:
Since Xdebug 2.6, the profiler also collects information about how much memory is being used, and which functions aGnd methods increased memory usage.
I'm not familiar with th...
ActiveRecord: size vs count
... don't know what you are doing, use size...
count
Resolves to sending a Select count(*)... query to the DB. The way to go if you don't need the data, but just the count.
Example: count of new messages, total elements when only a page is going to be displayed, etc.
length
Loads the required dat...
Install a Windows service using a Windows command prompt?
...ghts first!
To open with admin rights, right click 'Command Prompt' and select 'Run as administrator'.
Source:
http://coderamblings.wordpress.com/2012/07/24/how-to-install-a-windows-service-using-the-command-prompt/
shar...
Background color of text in SVG
...or to SVG elements. You can do it programmatically with d3.
var text = d3.select("text");
var bbox = text.node().getBBox();
var padding = 2;
var rect = self.svg.insert("rect", "text")
.attr("x", bbox.x - padding)
.attr("y", bbox.y - padding)
.attr("width", bbox.width + (padding*2))
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Is there a NumPy function to return the first index of something in an array?
...st element. Note also that where and nonzero return arrays, so you need to select the first element to get the index.
In [71]: np.argmax(a==2)
Out[71]: 2
In [72]: np.where(a==2)
Out[72]: (array([2], dtype=int64),)
In [73]: np.nonzero(a==2)
Out[73]: (array([2], dtype=int64),)
Time comparison
Ju...