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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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sed one-liner to convert all uppercase to lowercase?
...camelcase a sentence:
$ sed -r 's/\w+/\u&/g' <<< "Now is the time for all good men..." # Camel Case
Now Is The Time For All Good Men...
Note: Since the assumption is we have GNU extensions, we can also use the dash-r (extended regular expressions) option, which allows \w (word chara...
How can I shuffle the lines of a text file on the Unix command line or in a shell script?
...ely different. sort -R is deterministic. If you call it twice at different times on the same input you will get the same answer. shuf, on the other hand, produces randomized output, so it will most likely give different output on the same input.
– EfForEffort
F...
How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites
The question is how to format a JavaScript Date as a string stating the time elapsed similar to the way you see times displayed on Stack Overflow.
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Python list directory, subdirectory, and files
..., i'd like to show a nice example and comparison with listdir:
import os, time
def listFiles1(root): # listdir
allFiles = []; walk = [root]
while walk:
folder = walk.pop(0)+"/"; items = os.listdir(folder) # items = folders + files
for i in items: i=folder+i; (walk if os.pat...
How do you get assembler output from C/C++ source in gcc?
...best if debugging option is enabled for the object file (-g at compilation time) and the file hasn't been stripped.
Running file helloworld will give you some indication as to the level of detail that you will get by using objdump.
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How to set timeout on python's socket recv method?
I need to set timeout on python's socket recv method. How to do it?
10 Answers
10
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How to get current timestamp in string format in Java? “yyyy.MM.dd.HH.mm.ss”
How to get timestamp in string format in Java? "yyyy.MM.dd.HH.mm.ss"
7 Answers
7
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Why no generics in Go?
...onvenient but they come at a cost in complexity in the type system and run-time. We haven't yet found a design that gives value proportionate to the complexity, although we continue to think about it. Meanwhile, Go's built-in maps and slices, plus the ability to use the empty interface to construct ...
“Cloning” row or column vectors
Sometimes it is useful to "clone" a row or column vector to a matrix. By cloning I mean converting a row vector such as
9 A...