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How can i query for null values in entity framework?
...eral times. If this bug has affected you too, please visit the bug report on UserVoice and let Microsoft know that this bug has affected you as well.
Edit: This bug is being fixed in EF 4.5! Thanks everyone for upvoting this bug!
For backwards compatibility, it will be opt-in - you need manual...
When to use enumerateObjectsUsingBlock vs. for
...ly, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fast or faster t...
When should you not use virtual destructors?
Is there ever a good reason to not declare a virtual destructor for a class? When should you specifically avoid writing one?
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Is GridFS fast and reliable enough for production?
...
I use gridfs at work on one of our servers which is part of a price-comparing website with honorable traffic stats (arround 25k visitors per day). The server hasn't much ram, 2gigs, and even the cpu isn't really fast (Core 2 duo 1.8Ghz) but the s...
Writing a compiler in its own language
...nterpreter) for your language in some other language (usually Java or C). Once that is done, you can write a new version of the compiler in language Foo. You use the first bootstrap compiler to compile the compiler, and then use this compiled compiler to compile everything else (including future v...
Should I implement __ne__ in terms of __eq__ in Python?
...
Yes, that's perfectly fine. In fact, the documentation urges you to define __ne__ when you define __eq__:
There are no implied relationships
among the comparison operators. The
truth of x==y does not imply that x!=y
is false. Accordingly, when defining
__eq__(), on...
RabbitMQ / AMQP: single queue, multiple consumers for same message?
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Can I have each consumer receive the same messages? Ie, both consumers get message 1, 2, 3, 4, 5, 6? What is this called in AMQP/RabbitMQ speak? How is it normally configured?
No, not if the consumers are on the same queue. From RabbitMQ's A...
How to show google.com in an iframe?
I am trying to put google.com into an iframe on my website, this works with many other websites including yahoo. But it does not work with google as it just shows a blank iframe. Why does it not render? Are there any tricks to do that?
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npm install error - MSB3428: Could not load the Visual C++ component “VCBuild.exe”
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Try this from cmd line as Administrator
optional part, if you need to use a proxy:
set HTTP_PROXY=http://login:password@your-proxy-host:your-proxy-port
set HTTPS_PROXY=http://login:password@your-proxy-host:your-proxy-port
run this:
npm install -g --production windo...
How to redirect output with subprocess in Python?
...
UPDATE: os.system is discouraged, albeit still available in Python 3.
Use os.system:
os.system(my_cmd)
If you really want to use subprocess, here's the solution (mostly lifted from the documentation for subprocess):
p = subprocess.Popen(my_cmd, shell=True)
os.waitpid(p.pid, 0)
OT...