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How to delete duplicates on a MySQL table?
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Notice: this would keep the oldest duplicate record and would erase the newer ones. If you want to keep the newest you cannot do this with ALTER IGNORE.
– Haralan Dobrev
Oct 1 '12 at 10:26
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When should a class be Comparable and/or Comparator?
I have seen classes which implement both Comparable and Comparator . What does this mean? Why would I use one over the other?
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Service vs IntentService in the Android platform
... can be done with an IntentService that cannot be done with a Service (and vice-versa)?
11 Answers
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Determine version of Entity Framework I am using?
I believe there are two versions 1 and 2? And version 2 is referred to as Entity Framework 4.0?
10 Answers
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How to find all positions of the maximum value in a list?
... 0 for this is 2n, the list is iterated through 2x, once to determine max, and another time to find the positions of the max. A for loop that tracks the current max and its position might be more efficient for really long lists.
– radtek
Jan 8 '15 at 18:42
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What does “var FOO = FOO || {}” (assign a variable or an empty object to that variable) mean in Java
...s is used to create a namespace, i.e. a named object under which functions and variables can be created without unduly polluting the global object.
The reason why it's used is so that if you have two (or more) files:
var MY_NAMESPACE = MY_NAMESPACE || {};
MY_NAMESPACE.func1 = {
}
and
var MY_NAM...
Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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Why can't I reference my class library?
I have a solution that contains a website and a class library in Visual Studio 2008.
20 Answers
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Which concurrent Queue implementation should I use in Java?
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Basically the difference between them are performance characteristics and blocking behavior.
Taking the easiest first, ArrayBlockingQueue is a queue of a fixed size. So if you set the size at 10, and attempt to insert an 11th element, the insert statement will block until another thread remove...
Change C++/CLI project to another framework than 4.0 with vs2010
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This shows up when you press F1 in the Framework and References dialog:
By default for new projects, the targeted framework is set to .NET Framework 4. The IDE does not support modifying the targeted framework, but you can change it manually.
In the project file (.vcx...