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If vs. Switch Speed
Switch statements are typically faster than equivalent if-else-if statements (as e.g. descibed in this article ) due to compiler optimizations.
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How do I get the MAX row with a GROUP BY in LINQ query?
... (s => s.uid, tv => tv.uid, asdf => asdf.uid). Linq will automatically recognize it as selecting over elements of type Serial.
– Michael
Mar 17 '11 at 17:03
add a com...
Send and receive messages through NSNotificationCenter in Objective-C?
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@implementation TestClass
- (void) dealloc
{
// If you don't remove yourself as an observer, the Notification Center
// will continue to try and send notification objects to the deallocated
// object.
[[NSNotificationCenter defaultCenter] removeO...
Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...ustering options are also available.
In regards to AMQP, I would say a really cool feature is the "exchange", and the ability for it to route to other exchanges. This gives you more flexibility and enables you to create a wide array of elaborate routing typologies which can come in very handy when...
Android get color as string value
...olor(...)" and type it out again, use intellisense to complete the method call with the Android deprecated getColor call and you're good.
– Wes Winn
Apr 25 '17 at 23:00
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Using unset vs. setting a variable to empty
...t; unset var
/home/user1> echo $var
-bash: var: unbound variable
So really, it depends on how you are going to test the variable.
I will add that my preferred way of testing if it is set is:
[[ -n $var ]] # True if the length of $var is non-zero
or
[[ -z $var ]] # True if zero length
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NameError: global name 'xrange' is not defined in Python 3
...nchanged, and any
# range(...) replaced with list(range(...))
or replace all uses of xrange(...) with range(...) in the codebase and then use a different shim to make the Python 3 syntax compatible with Python 2:
try:
# Python 2 forward compatibility
range = xrange
except NameError:
p...
How to get a Docker container's IP address from the host
...n. Maybe provide two examples clearly labelled Linux and Windows. I literally just typed the example, checked the docs which also uses single quotes and then Googled the error. I'm sure I'm not alone.
– Wyck
Apr 15 '19 at 18:42
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PHP session lost after redirect
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First, carry out these usual checks:
Make sure session_start(); is called before any sessions are being called. So a safe bet would be to put it at the beginning of your page, immediately after the opening <?php declaration before anything else. Also ensure there are no whitespaces/tabs be...
There is already an open DataReader associated with this Command which must be closed first
...en iterating over the results of some query.
This can be easily solved by allowing MARS in your connection string. Add MultipleActiveResultSets=true to the provider part of your connection string (where Data Source, Initial Catalog, etc. are specified).
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