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Is there any difference between GROUP BY and DISTINCT
...the SQL Server is smart enough to realize that if you are using "Group By" and not using any aggregate functions, then what you actually mean is "Distinct" - and therefore it generates an execution plan as if you'd simply used "Distinct."
However, I think it's important to note Hank's response as w...
What is the difference between declarative and procedural programming paradigms?
What is the difference between the declarative and procedural programming paradigms? Could you please provide some examples?
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Cannot delete directory with Directory.Delete(path, true)
...he workings of Directory.Delete. Please read the comments for this answer, and other answers to this question.
I ran into this problem before.
The root of the problem is that this function does not delete files that are within the directory structure. So what you'll need to do is create a functi...
Switch statement: must default be the last case?
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The C99 standard is not explicit about this, but taking all facts together, it is perfectly valid.
A case and default label are equivalent to a goto label. See 6.8.1 Labeled statements. Especially interesting is 6.8.1.4, which enables...
How do I edit /etc/sudoers from a script?
...ripts in debian packages. thanks! Since this is always root, it gets short and handy: echo "$CONFIGLINE" | (EDITOR="tee -a" visudo)
– Boris Däppen
Jan 5 '16 at 16:05
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What is the correct answer for cout
...en updated. In particular:
In a shift operator expression E1<<E2 and E1>>E2, every value computation and side-effect of E1 is sequenced before every value computation and side effect of E2.
Which means that it requires the code to produce result b, which outputs 01.
See P0145R3 Re...
How to perform .Max() on a property of all objects in a collection and return the object with maximu
...rating through the data, remembering the maximum element we've seen so far and the maximum value it produced under the projection.
In your case you'd do something like:
var item = items.MaxBy(x => x.Height);
This is better (IMO) than any of the solutions presented here other than Mehrdad's se...
Test for equality among all elements of a single vector
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I use this method, which compares the min and the max, after dividing by the mean:
# Determine if range of vector is FP 0.
zero_range <- function(x, tol = .Machine$double.eps ^ 0.5) {
if (length(x) == 1) return(TRUE)
x <- range(x) / mean(x)
isTRUE(all.eq...
Why both no-cache and no-store should be used in HTTP response?
...d response you may have, on every request.
must-revalidate, on the other hand, only needs to revalidate when the resource is considered stale.
If the server says that the resource is still valid then the cache can respond with its representation, thus alleviating the need for the server to resend ...
A simple scenario using wait() and notify() in java
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The wait() and notify() methods are designed to provide a mechanism to allow a thread to block until a specific condition is met. For this I assume you're wanting to write a blocking queue implementation, where you have some fixed size ...