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How does Hadoop process records split across block boundaries?
...mapper already knows if it neds to discard the first line or not.
So basically if you have 2 lines of each 100Mb in the same file, and to simplify let's say the split size is 64Mb. Then when the input splits are calculated, we will have the following scenario:
Split 1 containing the path and the ...
What is the difference between atomic / volatile / synchronized?
How do atomic / volatile / synchronized work internally?
7 Answers
7
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node.js child process - difference between spawn & fork
... node process. You can add listeners for the process you have spawned, to allow your code interact with the spawned process, but no new V8 instance is created(unless of course your command is another Node command, but in this case you should use fork!) and only one copy of your node module is activ...
Scala equivalent of Java java.lang.Class Object
...: java.lang.Class[C] = class C
scala> c.getClass
res1: java.lang.Class[_] = class C
That is why the following will not work:
val xClass: Class[X] = new X().getClass //it returns Class[_], nor Class[X]
val integerClass: Class[Integer] = new Integer(5).getClass //similar error
There is a ticket...
Max return value if empty query
...jects in the list are a non-nullable type: docs.microsoft.com/en-us/dotnet/api/…
– Dominus.Vobiscum
Jun 12 at 18:00
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How to access property of anonymous type in C#?
...null in three different situations!
o is null, so there is no object at all
o is non-null but doesn't have a property Foo
o has a property Foo but its real value happens to be null.
So this is not equivalent to the earlier examples, but may make sense if you want to treat all three cases the sa...
Django templates: verbose version of a choice
... (universal), though - unless you know a way to iterate in a template over all get_FOO_display methods of a model object :) I'm a bit too lazy for writing non-generic templates ;) Moreover, the docs say it's a model instance's method. Therefore it'd have to be a model form bound to an existing obj...
Calling filter returns [duplicate]
...ten) want to do the filtering in a lazy sense -- You don't need to consume all of the memory to create a list up front, as long as the iterator returns the same thing a list would during iteration.
If you're familiar with list comprehensions and generator expressions, the above filter is now (alm...
How to log source file name and line number in Python
...='%Y-%m-%d:%H:%M:%S',
level=logging.DEBUG)
logger = logging.getLogger(__name__)
logger.debug("This is a debug log")
logger.info("This is an info log")
logger.critical("This is critical")
logger.error("An error occurred")
Generates this output:
2017-06-06:17:07:02,158 DEBUG [log.py:11] Thi...
Error in exception handler. - Laravel
It's a Laravel-install related question. I have a public-facing Unix server setup:
6 Answers
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