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How do ACID and database transactions work?
... achieve the ACID properties.
Atomicity means that you can guarantee that all of a transaction happens, or none of it does; you can do complex operations as one single unit, all or nothing, and a crash, power failure, error, or anything else won't allow you to be in a state in which only some of th...
Import Maven dependencies in IntelliJ IDEA
I have a small question about IntelliJ IDEA 11. I just imported a project from subversion - its a maven project. But I have a problem in maven library dependencies so that I can't include all maven dependencies automatically - IDEA shows dependency errors only when I open that class/ Thats what I ge...
Collisions when generating UUIDs in JavaScript?
...rom Math.random(). For some browsers the entropy is as low as just 41 bits all together. Calling Math.random() multiple times won't raise the entropy. If you really want unique v4 UUIDs you need to use a cryptographically strong RNG that produces at least 122bit entropy per UUID generated.
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How to get milliseconds from LocalDateTime in Java 8
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Sure, if all you need is seconds, not milliseconds.
– Stuart Marks
May 30 '14 at 17:23
1
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How to know if other threads have finished?
...Thread to complete, or
Check Thread.isAlive() in a polling fashion -- generally discouraged -- to wait until each Thread has completed, or
Unorthodox, for each Thread in question, call setUncaughtExceptionHandler to call a method in your object, and program each Thread to throw an uncaught Exception...
How to check for the type of a template parameter?
...::is_same<T, animal>::value) { /* ... */ } // optimizable...
}
Usually, that's a totally unworkable design, though, and you really want to specialize:
template <typename T> void foo() { /* generic implementation */ }
template <> void foo<animal>() { /* specific for T ...
Most common way of writing a HTML table with vertical headers?
Hi all it's been a while since I've asked something, this is something that has been bothering me for a while, the question itself is in the title:
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SQL RANK() versus ROW_NUMBER()
...ular ordering value.
RANK and DENSE_RANK are deterministic in this case, all rows with the same value for both the ordering and partitioning columns will end up with an equal result, whereas ROW_NUMBER will arbitrarily (non deterministically) assign an incrementing result to the tied rows.
Examp...
How do I open an old MVC project in Visual Studio 2012 or Visual Studio 2013?
...unsupported MVC project in Visual Studio 2012 or Visual Studio 2013 is actually pretty easy to accomplish with two steps. In fact, as bytebender’s comment indicates, these same steps should apply to and work for MVC 1 projects. However, I haven’t tested them and therefore cannot guarantee that t...
Difference between 'python setup.py install' and 'pip install'
I have an external package I want to install into my python virtualenv from a tar file.
What is the best way to install the package?
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