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Installing Java on OS X 10.9 (Mavericks)
....8 (Mountain Lion). When I upgraded it to Mac OS X v10.9 (Mavericks) and ran java -version in the terminal, it showed:
...
Shared-memory objects in multiprocessing
...r array), place that in shared memory, wrap it with multiprocessing.Array, and pass that to your functions. This answer shows how to do that.
If you want a writeable shared object, then you will need to wrap it with some kind of synchronization or locking. multiprocessing provides two methods of do...
Download a file with Android, and showing the progress in a ProgressDialog
...t gets updated. For this I need a simple function that can download a file and show the current progress in a ProgressDialog . I know how to do the ProgressDialog , but I'm not sure how to display the current progress and how to download the file in the first place.
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SQL - Update multiple records in one query
...e syntax
UPDATE config t1 JOIN config t2
ON t1.config_name = 'name1' AND t2.config_name = 'name2'
SET t1.config_value = 'value',
t2.config_value = 'value2';
Here is SQLFiddle demo
or conditional update
UPDATE config
SET config_value = CASE config_name
WH...
SQL Server SELECT into existing table
I am trying to select some fields from one table and insert them into an existing table from a stored procedure. Here is what I am trying:
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Why is printing to stdout so slow? Can it be sped up?
...ement. After some recent painfully slow logging I decided to look into it and was quite surprised to find that almost all the time spent is waiting for the terminal to process the results.
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Why does the JVM still not support tail-call optimization?
...tail-call-optimizations , there seems to be a prototype implementation and MLVM has listed the feature as "proto 80%" for some time now.
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curl : (1) Protocol https not supported or disabled in libcurl
...g to install the Rails environments on Ubuntu 11.04. When I launch the command rvm install 1.9.2 --with-openssl-dir=/usr/local the following error is received:
...
Multiple inheritance/prototypes in JavaScript
... false,
}));
}
Explanation
A proxy object consists of a target object and some traps, which define custom behavior for fundamental operations.
When creating an object which inherits from another one, we use Object.create(obj). But in this case we want multiple inheritance, so instead of obj I ...
How can you represent inheritance in a database?
...ar basis.
The database will not be able to enforce which attributes apply and which don't, since there is no metadata to define which attributes belong to which subtypes.
You also cannot enforce NOT NULL on attributes of a subtype that should be mandatory. You would have to handle this in your app...