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No ConcurrentList in .Net 4.0?
...or all items 0-63, and a size-128 array for items 64-127. The overhead of selecting which one of two arrays to use, plus a memory barrier if desired, would be less than the overhead of even the most efficient reader-writer lock imaginable. Writes should probably use locks (lock-free would be possi...
How to add a custom right-click menu to a webpage?
... asking anyone to write the code for me, just to explain how to do it. The selected answer did that perfectly.
– I wrestled a bear once.
Apr 8 '15 at 23:48
6
...
What is the significance of 1/1/1753 in SQL Server?
...imply use the Gregorian Calendar.
So with the greater range of datetime2
SELECT CONVERT(VARCHAR, DATEADD(DAY,-5,CAST('1752-09-13' AS DATETIME2)),100)
Returns
Sep 8 1752 12:00AM
One final point with the datetime2 data type is that it uses the proleptic Gregorian calendar projected backwards t...
Why are joins bad when considering scalability?
...en so can you.
There are many reasons not to denomalize. First, speed of select queries is not the only or even main concern with databases. Integrity of the data is the first concern. If you denormalize then you have to put into place techniques to keep the data denormalized as the parent data ch...
How to upload a file in Django? [closed]
...ss DocumentForm(forms.Form):
docfile = forms.FileField(
label='Select a file',
help_text='max. 42 megabytes'
)
4. View: myproject/myapp/views.py
A view where all the magic happens. Pay attention how request.FILES are handled. For me, it was really hard to spot the fact tha...
initializer_list and move semantics
... std::forward<Ts>(ts)... };
}
};
//
// delegation function which selects the correct maker
//
template<class Array, class...Ts>
auto make(Ts&&...ts)
{
auto m = maker<Array>();
return m(std::forward<Ts>(ts)...);
}
// vectors and arrays of non-copyable types
us...
How to use Elasticsearch with MongoDB?
...ng bumped up when you update.
echo "mongodb-10gen hold" | sudo dpkg --set-selections
Start the MongoDB service.
sudo service mongodb start
Your database files default to /var/lib/mongo and your log files to /var/log/mongo.
Create a database through the mongo shell and push some dummy data int...
Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie
... If the computer is restarted and "Reopen windows when logging back in" is selected, the reopened windows may not see the variables (Perhaps they are opened before the agent is run). Also, if you log in via ssh, the variables will not be set (so you'll need to set them in ~/.bash_profile). Finally, ...
Spring @Transactional - isolation, propagation
...ion. I think if you understand the dirty reads concept you will be able to select a good option.
Example of when a dirty read can occur:
thread 1 thread 2
| |
write(x) |
| |
| read(x)
| |
rollback |
v v...
How do you specify the Java compiler version in a pom.xml file?
... Which way is "best"? This one is less verbose compared to the selected answer, but it seems sort of hidden. Even the Maven site documentation shows using the plugin.
– mkobit
Oct 15 '15 at 16:34
...