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Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...s a more complete version that shows more differences between [ (aka test) and [[.
The following table shows that whether a variable is quoted or not, whether you use single or double brackets and whether the variable contains only a space are the things that affect whether using a test with or wit...
How to concatenate and minify multiple CSS and JavaScript files with Grunt.js (0.3.x)
Note: This question is only relevant for Grunt 0.3.x and has been left for reference. For help with the latest Grunt 1.x release please see my comment below this question.
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Simple way to calculate median with MySQL
What's the simplest (and hopefully not too slow) way to calculate the median with MySQL? I've used AVG(x) for finding the mean, but I'm having a hard time finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but ...
Checking for a dirty index or untracked files with Git
...;/dev/null| grep "^M" | wc -l)
# Get number of files that are uncommitted and not added
expr $(git status --porcelain 2>/dev/null| grep "^ M" | wc -l)
# Get number of total uncommited files
expr $(git status --porcelain 2>/dev/null| egrep "^(M| M)" | wc -l)
Note: The 2>/dev/null filters...
Xcode 6 Bug: Unknown class in Interface Builder file
I upgraded to Xcode 6 beta 4 and now my App continuously crashes with the message
52 Answers
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What is the strict aliasing rule?
... ability to give aliasing warnings, sometimes giving us a friendly warning and sometimes not.)
To see why this behavior is undefined, we have to think about what the strict aliasing rule buys the compiler. Basically, with this rule, it doesn't have to think about inserting instructions to refresh th...
Truncate Two decimal places without rounding
Lets say I have a value of 3.4679 and want 3.46, how can I truncate to two decimal places that without rounding up?
21 Answ...
How to delete duplicate rows in SQL Server?
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I like CTEs and ROW_NUMBER as the two combined allow us to see which rows are deleted (or updated), therefore just change the DELETE FROM CTE... to SELECT * FROM CTE:
WITH CTE AS(
SELECT [col1], [col2], [col3], [col4], [col5], [col6]...
What is the difference between gravity and layout_gravity in Android?
I know we can set the following values to the android:gravity and android:layout_gravity properties:
20 Answers
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PUT vs. POST in REST
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Overall:
Both PUT and POST can be used for creating.
You have to ask "what are you performing the action to?" to distinguish what you should be using. Let's assume you're designing an API for asking questions. If you want to use POST then y...