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What is the difference between buffer and cache memory in Linux?
...er caches. Since 2.4, the page and buffer cache are unified and Buffers is raw disk blocks not represented in the page cache—i.e., not file data. The Buffers metric is thus of minimal importance. On most systems, Buffers is often only tens of megabytes.
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How do I create a unique constraint that also allows nulls?
...o use a negative number, to put the "surrogate NULLs" only in the negative range, and the "real values" only in the positive range. Alternately, the following pattern could be used. In table Issue (where IssueID is the PRIMARY KEY), there may or may not be a TicketID, but if there is one, it must be...
How do Python's any and all functions work?
...onsumed. For example,
>>> multiples_of_6 = (not (i % 6) for i in range(1, 10))
>>> any(multiples_of_6)
True
>>> list(multiples_of_6)
[False, False, False]
Here, (not (i % 6) for i in range(1, 10)) is a generator expression which returns True if the current number within...
Counting Chars in EditText Changed Listener
... it.
start: This is the index of where the new text will be inserted. If a range is selected, then it is the beginning index of the range.
count: This is the length of selected text that is going to be replaced. If nothing is selected then count will be 0.
after: this is the length of the text to be...
An efficient way to transpose a file in Bash
...es an array for the input lines after parsing each line as JSON, and -r (--raw-output) outputs the contents of strings instead of JSON string literals. The / operator is overloaded to split strings.
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Understanding the map function
...tr(x) for x in iterable ]
b = time.clock() - b
print(a,b)
test1(range(2000000)) # Prints ~1.7e-5s ~8s
test2(range(2000000)) # Prints ~9s ~8s
As you can see initializing the map function takes almost no time at all. However iterating through the map object takes longer than sim...
Parallel foreach with asynchronous lambda
...xception(exceptions);
}
}
}
Usage example:
await Enumerable.Range(1, 10000).ParallelForEachAsync(async (i) =>
{
var data = await GetData(i);
}, maxDegreeOfParallelism: 100);
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How to compare dates in datetime fields in Postgresql?
I have been facing a strange scenario when comparing between dates in postgresql(version 9.2.4 in windows). I have a column in my table say update_date with type 'timestamp without timezone'. Client can search over this field with only date (i.e: 2013-05-03) or date with time (i.e: 2013-05-03 12:20:...
Measuring text width to be drawn on Canvas ( Android )
Is there a method which returns the width ( in pixels ) of a text to be drawn on an Android canvas using the drawText() method according to the Paint used to draw it?
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Difference between ApiController and Controller in ASP.NET MVC
...ing Controllers methods returning ActionResult mixed with others returning raw/serialized/IHttpActionResult data can be very confusing from a developer perspective, expecially if you're not working alone and need to bring other developers to speed with that hybrid approach.
The best technique I've ...