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Bootstrap Dropdown menu is not working
...n my machine. Anyone have any ideas? I have been staring at it for an hour and can't seem to figure out what the problem is.
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Apache Spark: map vs mapPartitions?
What's the difference between an RDD's map and mapPartitions method? And does flatMap behave like map or like mapPartitions ? Thanks.
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How does Hadoop process records split across block boundaries?
...nteresting question, I spent some time looking at the code for the details and here are my thoughts. The splits are handled by the client by InputFormat.getSplits, so a look at FileInputFormat gives the following info:
For each input file, get the file length, the block size and calculate the spli...
Why I can't change directories using “cd”?
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Shell scripts are run inside a subshell, and each subshell has its own concept of what the current directory is. The cd succeeds, but as soon as the subshell exits, you're back in the interactive shell and nothing ever changed there.
One way to get around this is t...
What is the idiomatic Go equivalent of C's ternary operator?
In C/C++ (and many languages of that family), a common idiom to declare and initialize a variable depending on a condition uses the ternary conditional operator :
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PHP - Extracting a property from an array of objects
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this is the correct solution and will lead to the fact that every upcoming maintainer will be "wtf"'d :D
– Andreas Klinger
Jul 13 '09 at 11:56
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Why does “return list.sort()” return None, not the list?
... l = sorted(l.append('2')) (I just added semi-colon so you could cut/paste and run)
– JGFMK
May 30 '18 at 9:54
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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Function in JavaScript that can be called only once
...y once, in each time after the first it won't be executed. I know from C++ and Java about static variables that can do the work but I would like to know if there is a more elegant way to do this?
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Why fragments, and when to use fragments instead of activities?
In Android API 11+, Google has released a new class called Fragment .
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