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When should I use a struct rather than a class in C#?
...lass in C#? My conceptual model is that structs are used in times when the item is merely a collection of value types . A way to logically hold them all together into a cohesive whole.
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Why do this() and super() have to be the first statement in a constructor?
Java requires that if you call this() or super() in a constructor, it must be the first statement. Why?
19 Answers
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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
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Bottom Line
Use either COUNT(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely d...
How does the new automatic reference counting mechanism work?
Can someone briefly explain to me how ARC works? I know it's different from Garbage Collection, but I was just wondering exactly how it worked.
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What is the purpose of the HTML “no-js” class?
...gines, in the HTML5 Boilerplate , in various frameworks and in plain php sites there is the no-js class added onto the <HTML> tag.
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Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...e=1 and code=2 . If the memory address was 0x00000000 , I'd have a clue it is a NullPointer.
23 Answers
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eclipse stuck when building workspace
I am using eclipse 3.4.1 Java EE under Vista. It seems to like getting stuck when building my workspace. Canceling the build doesn't seem to do anything as well.
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Why doesn't .NET/C# optimize for tail-call recursion?
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JIT compilation is a tricky balancing act between not spending too much time doing the compilation phase (thus slowing down short lived applications considerably) vs. not doing enough analysis to keep the application competiti...
How do I connect to a MySQL Database in Python?
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Connecting to MYSQL with Python 2 in three steps
1 - Setting
You must install a MySQL driver before doing anything. Unlike PHP, Only the SQLite driver is installed by default with Python. The most used package to do so is MySQLdb but it's hard ...
Using the Android Application class to persist data
...om what I can tell, any orientation change in the application (in the activity, to be more precise) causes a complete destruction and recreation of the activity. Based on my findings, the Application class does not have the same life-cycle (i.e. it is, for all intents and purposes, always instantia...