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Checking Bash exit status of several commands efficiently
...mand2 are environment variables that have been set to a command.
function mytest {
"$@"
local status=$?
if (( status != 0 )); then
echo "error with $1" >&2
fi
return $status
}
mytest "$command1"
mytest "$command2"
...
C# equivalent of the IsNull() function in SQL Server
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It's called the null coalescing (??) operator:
myNewValue = myValue ?? new MyValue();
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How to install multiple python packages at once using pip
... answers, you can use the option --no-cache-dir to disable caching in pip. My virtual machine was crashing when installing many packages at once with pip install -r requirements.txt. What solved for me was:
pip install --no-cache-dir -r requirements.txt
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using lodash .groupBy. how to add your own keys for grouped output?
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Very nifty, but hard to wrap my head around. Can you explain the steps in between, especially the pairing and zipping (and the double zip, since _.object is an alias for _.zipObject).
– Benny Bottema
Jul 31 '15 at 9...
How to make the first option of selected with jQuery
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I recant my previous statement, was getting ahead of myself. $("#target").val("option:first"); works most everywhere but IE6 $("target").val($("#target option:first").val()); will work in IE6, because you are literally looking up the ...
How to clear an ImageView in Android?
I am reusing ImageView s for my displays, but at some point I don't have values to put it.
17 Answers
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Android: Go back to previous activity
...g about exiting an activity you need just for a bit .. e.g. OCR scanner in my case. Thanks!
– Gene Bo
Apr 9 '15 at 22:31
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How do I query for all dates greater than a certain date in SQL Server?
...here A.Date >= '2010-04-01'
it will do the conversion for you, but in my opinion it is less readable than explicitly converting to a DateTime for the maintenance programmer that will come after you.
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What is the meaning of the term arena in relation to memory?
...e:
char * arena = malloc(HUGE_NUMBER);
unsigned int current = 0;
void * my_malloc(size_t n) { current += n; return arena + current - n; }
The point is that you get full control over how the memory allocation works. The only thing outside your control is the single library call for the initial a...
What is the difference between partitioning and bucketing a table in Hive ?
...ok at how data is stored in hive.
Let's say you have a table
CREATE TABLE mytable (
name string,
city string,
employee_id int )
PARTITIONED BY (year STRING, month STRING, day STRING)
CLUSTERED BY (employee_id) INTO 256 BUCKETS
then hive will store data in a directory...