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Is a GUID unique 100% of the time?
...ge that the probability of the same number being
generated twice is very small. For
example, consider the observable
universe, which contains about 5×1022
stars; every star could then have
6.8×1015 universally unique GUIDs.
From Wikipedia.
These are some good articles on how a GUID is made (for ...
Why use JUnit for testing?
Maybe my question is a newbie one, but I can not really understand the circumstances under which I would use junit ?
11 An...
Add and Remove Views in Android Dynamically?
...app like on the original stock Android contacts screen where you press a small icon on the right side of a field and it adds or deletes a field which consists of a TextView and an editTextView (from what I can see).
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CSS 100% height with padding/margin
...about IE compatibility, I unfortunately have to. This solution didn't initially work under IE6. Adding Dean Edwards' IE9.js to the page made this work. Now I just have to hope and pray that the relative/absolute positioning doesn't screw with something in a child element...
– C...
How do you know what to test when writing unit tests? [closed]
Using C#, I need a class called User that has a username, password, active flag, first name, last name, full name, etc.
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How big can a MySQL database get before performance starts to degrade
...us first on your indexes, then have a server admin look at your OS, and if all that doesn't help it might be time to implement a master/slave configuration.
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What is the point of function pointers?
...nction pointers. I guess it may be useful in some cases (they exist, after all), but I can't think of a case where it's better or unavoidable to use a function pointer.
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What is the point of a “Build Server”? [closed]
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The reason given is actually a huge benefit. Builds that go to QA should only ever come from a system that builds only from the repository. This way build packages are reproducible and traceable. Developers manually building code for anything except...
Why doesn't java.lang.Number implement Comparable? [duplicate]
...2 += 0.1d;
}
System.out.println(d2 - d1);
and you'll be left with some small difference.
So back to the issue of making Number Comparable. How would you implement it? Using something like doubleValue() wouldn't do it reliably. Remember the Number subtypes are:
Byte;
Short;
Integer;
Long;
Ato...
How to execute a raw update sql with dynamic binding in rails
...
It doesn't look like the Rails API exposes methods to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st...