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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...
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...
Find out who is locking a file on a network share
...an even use Action -> Connect to another computer to the file on a NAS, and it even works with our linux based NAT! Why didn't I try this earlier?
– olorin
Sep 24 '10 at 12:51
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Running PostgreSQL in memory only
...y for this particular question: It's a bad idea to mix with valuable data (and thanks for the warning). For unit-testing with a dedicated DB cluster, a ramdisk is fine.
– Erwin Brandstetter
Jul 12 '15 at 0:32
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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 ...
Parse a .py file, read the AST, modify it, then write back the modified source code
...on source code. Basically I want to read a .py file, generate the AST , and then write back the modified python source code (i.e. another .py file).
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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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Efficient string concatenation in C++
I heard a few people expressing worries about "+" operator in std::string and various workarounds to speed up concatenation. Are any of these really necessary? If so, what is the best way to concatenate strings in C++?
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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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