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When to use Common Table Expression (CTE)
I have begun reading about Common Table Expression and cannot think of a use case where I would need to use them. They would seem to be redundant as the same can be done with derived tables. Is there something I am missing or not understanding well? Can someone give me a simple example of limitati...
SPAN vs DIV (inline-block)
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According to the HTML spec, <span> is an inline element and <div> is a block element. Now that can be changed using the display CSS property but there is one issue: in terms of HTML validation, you can't put block elements inside inline elements so:
<p>...<div>f...
What is wrong with using goto? [duplicate]
I was ramdomming through xkcd and saw this one (if also read some negative texts about them some years ago):
What is actually wrong with it? Why are goto's even possible in C++ then?
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What is the purpose of Node.js module.exports and how do you use it?
What is the purpose of Node.js module.exports and how do you use it?
12 Answers
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Is it safe to check floating point values for equality to 0?
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It is safe to expect that the comparison will return true if and only if the double variable has a value of exactly 0.0 (which in your original code snippet is, of course, the case). This is consistent with the semantics of the == operator. a == b means "a is equal to b".
It is not sa...
What is the difference between char s[] and char *s?
...o world";
will place "Hello world" in the read-only parts of the memory, and making s a pointer to that makes any writing operation on this memory illegal.
While doing:
char s[] = "Hello world";
puts the literal string in read-only memory and copies the string to newly allocated memory on the...
What is the difference between a heuristic and an algorithm?
What is the difference between a heuristic and an algorithm?
12 Answers
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Linux: compute a single hash for a given folder & contents?
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If there is a whole directory tree, you're probably better off using find and xargs. One possible command would be
find path/to/folder -type f -print0 | sort -z | xargs -0 sha1sum | sha1sum
And, finally, if you also need to take account of permissions and empty directories:
(find path/to/folde...
Folder is locked and I can't unlock it
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Right click on your Subversion working directory folder, and select TortoiseSVN->Clean Up from the Context Menu. This will recurse it's way through your working directory and cleanup any incomplete actions, remove the local locks (which is different from using Subversion locking...
Conditional formatting based on another cell's value
...low, it actually means "B{current_row}", so for C5 it's B5, for C6 it's B6 and so on. Unless you specify $B$5 - then you refer to one specific cell.
This is supported in Google Sheets as of 2015:
https://support.google.com/drive/answer/78413#formulas
In your case, you will need to set conditiona...