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Test for existence of nested JavaScript object key
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You have to do it step by step if you don't want a TypeError because if one of the members is null or undefined, and you try to access a member, an exception will be thrown.
You can either simply catch the exception, or make a function to test the existence of multiple levels, some...
How to see log files in MySQL?
I've read that Mysql server creates a log file where it keeps a record of all activities - like when and what queries execute.
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Add single element to array in numpy
...array which can be the old array with the appended element.
I think it's more normal to use the proper method for adding an element:
a = numpy.append(a, a[0])
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What is the difference between float and double?
...ost cases, float and double seem to be interchangeable, i.e. using one or the other does not seem to affect the results. Is this really the case? When are floats and doubles interchangeable? What are the differences between them?
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Java Set retain order?
Does a Java Set retain order? A method is returning a Set to me and supposedly the data is ordered but iterating over the Set, the data is unordered. Is there a better way to manage this? Does the method need to be changed to return something other than a Set?
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PostgreSQL LIKE query performance variations
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FTS does not support LIKE
The previously accepted answer was incorrect. Full Text Search with its full text indexes is not for the LIKE operator at all, it has its own operators and doesn't work for arbitrary strings. It operates on words ba...
How to measure elapsed time in Python?
... think I'm using the timeit module wrong, but the docs are just confusing for me.
35 Answers
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What's onCreate(Bundle savedInstanceState)
...an be passed back to onCreate if the activity needs to be recreated (e.g., orientation change) so that you don't lose this prior information. If no data was supplied, savedInstanceState is null.
... you
should use the onPause() method to write any persistent data (such as
user edits) to stor...
How to pass objects to functions in C++?
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Rules of thumb for C++11:
Pass by value, except when
you do not need ownership of the object and a simple alias will do, in which case you pass by const reference,
you must mutate the object, in which case, use pass by a non-const lvalue re...
Writing string to a file on a new line every time
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Use "\n":
file.write("My String\n")
See the Python manual for reference.
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