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Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...rs, but there's one aspect of these languages that I've never really understood. I've obviously used regular casts i.e.
8 A...
Spark java.lang.OutOfMemoryError: Java heap space
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I have a few suggestions:
If your nodes are configured to have 6g maximum for Spark (and are leaving a little for other processes), then use 6g rather than 4g, spark.executor.memory=6g. Make sure you're using as much memory as possible by checking the UI (it will say how much mem...
What is object serialization?
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Serialization is the conversion of an object to a series of bytes, so that the object can be easily saved to persistent storage or streamed across a communication link. The byte stream can then be deserialized - converted into a replica of the original object.
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What's wrong with foreign keys?
...at he'd barely ever used a foreign key (if I remember correctly). However, to me they seem pretty vital to avoid duplication and subsequent data integrity problems throughout your database.
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Running shell command and capturing the output
I want to write a function that will execute a shell command and return its output as a string , no matter, is it an error or success message. I just want to get the same result that I would have gotten with the command line.
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How to add a changed file to an older (not last) commit in Git
...last hour and committed them step by step, but I just realized I've forgot to add a changed file some commits ago.
4 Answer...
What is the Git equivalent for revision number?
We use SVN at work, but for my personal projects I decided to use Git. So I installed Git yesterday, and I wonder what is the revision number equivalent in Git .
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What's the difference between Perl's backticks, system, and exec?
...your perl script is continued after the command has finished.
In contrary to system the return value is STDOUT of the command.
qx// is equivalent to backticks.
You can find documentation about it in perlop, because unlike system and execit is an operator.
Other ways
What is missing from the...
Odd behavior when Java converts int to byte?
.... (The char type is unsigned, and the concept of a sign is not applicable to boolean.)
In this number scheme the most significant bit specifies the sign of the number. If more bits are needed, the most significant bit ("MSB") is simply copied to the new MSB.
So if you have byte 255: 11111111
and ...
Using global variables in a function
...ctions by declaring it as global within each function that assigns a value to it:
globvar = 0
def set_globvar_to_one():
global globvar # Needed to modify global copy of globvar
globvar = 1
def print_globvar():
print(globvar) # No need for global declaration to read value of glob...