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NSString property: copy or retain?
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For attributes whose type is an immutable value class that conforms to the NSCopying protocol, you almost always should specify copy in your @property declaration. Specifying retain is something you almost never want in such a situation.
Here's why ...
When to use Hadoop, HBase, Hive and Pig?
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MapReduce is just a computing framework. HBase has nothing to do with it. That said, you can efficiently put or fetch data to/from HBase by writing MapReduce jobs. Alternatively you can write sequential programs using other HBase APIs,...
How to find out client ID of component for ajax update/render? Cannot find component with expression
The following code is inspired from PrimeFaces DataGrid + DataTable Tutorials and put into a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout> . Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
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Easiest way to detect Internet connection on iOS?
I know this question will appear to be a dupe of many others, however, I don't feel the simple case is well explained here. Coming from an Android and BlackBerry background, making requests through HTTPUrlConnection instantly fail if there is no connection available. This seems like completely san...
Does pandas iterrows have performance issues?
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Generally, iterrows should only be used in very, very specific cases. This is the general order of precedence for performance of various operations:
1) vectorization
2) using a custom cython routine
3) apply
a) reductions that can be performed in cython
b) iteration in python space
4) it...
How to do a FULL OUTER JOIN in MySQL?
I want to do a Full Outer Join in MySQL. Is this possible? Is a Full Outer Join supported by MySQL?
15 Answers
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Make function wait until element exists
I'm trying to add a canvas over another canvas – how can I make this function wait to start until the first canvas is created?
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What is causing “Unable to allocate memory for pool” in PHP?
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Probably is APC related.
For the people having this problem, please specify you .ini settings. Specifically your apc.mmap_file_mask setting.
For file-backed mmap, it should be set to something like:
apc.mmap_file_mask=/tmp/apc.XXX...
Accessing class variables from a list comprehension in the class definition
How do you access other class variables from a list comprehension within the class definition? The following works in Python 2 but fails in Python 3:
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Changing default encoding of Python?
... console. But in the Eclipse PyDev IDE, the default character encoding is set to UTF-8 , and I'm fine.
11 Answers
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