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What is the purpose of Flask's context stacks?
I've been using the request/application context for some time without fully understanding how it works or why it was designed the way it was. What is the purpose of the "stack" when it comes to the request or application context? Are these two separate stacks, or are they both part of one stack? Is ...
What is the reason for performing a double fork when creating a daemon?
...hon. I've found the following question , which has some good resources in it which I am currently following, but I'm curious as to why a double fork is necessary. I've scratched around google and found plenty of resources declaring that one is necessary, but not why.
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Compare two MySQL databases [closed]
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If you're working with small databases I've found running mysqldump on both databases with the --skip-comments and --skip-extended-insert options to generate SQL scripts, then running diff on the SQL scripts works pretty well.
By skipping comm...
When to use Hadoop, HBase, Hive and Pig?
What are the benefits of using either Hadoop or HBase or Hive ?
16 Answers
16
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How can I pair socks from a pile efficiently?
...iring the socks from the clean laundry and figured out the way I was doing it is not very efficient. I was doing a naive search — picking one sock and "iterating" the pile in order to find its pair. This requires iterating over n/2 * n/4 = n 2 /8 socks on average.
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What's the best way to check if a file exists in C?
...p the access() function, found in unistd.h. You can replace your function with
if( access( fname, F_OK ) != -1 ) {
// file exists
} else {
// file doesn't exist
}
You can also use R_OK, W_OK, and X_OK in place of F_OK to check for read permission, write permission, and execute permission ...
Is it good practice to use the xor operator for boolean checks? [closed]
I personally like the exclusive or , ^ , operator when it makes sense in the context of boolean checks because of its conciseness. I much prefer to write
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What is the instanceof operator in JavaScript?
The instanceof keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that JavaScript is not an object-oriented programming language.
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Android: Storing username and password?
...sword to be used inside an Android application, what is the best way to do it? Is it through the preferences screen (but what if the user misses this?), or pop up a dialog box and ask the user for the credentials? If so, I do have to maintain state for the application. How would I do this?
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What are the downsides to using Dependency Injection? [closed]
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A couple of points:
DI increases complexity, usually by increasing the number of classes since responsibilities are separated more, which is not always beneficial
Your code will be (somewhat) coupled to the dependency injection framework you use (or more generally ...