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How do I create a URL shortener?
...two character checksum to the url. That would prevent direct iteration of all the urls in your system. Something simple like f(checksum(id) % (62^2)) + f(id) = url_id
– koblas
Sep 4 '10 at 13:53
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How do I get the information from a meta tag with JavaScript?
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What you really want is 'let' to keep them locally defined ;)
– tommed
Mar 23 '15 at 21:54
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What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
What is the equivalent of 'describe table' in SQL Server?
...u want, though unfortunately you have to query the views and join them manually.
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Switching to landscape mode in Android Emulator
...inux.
For Mac users, you only need to use the fn key if the setting "Use all F1, F2 etc. keys as function keys" (under System Preferences -> Keyboard) is checked.
left-ctrl+F11on Windows 7
It works fine in Windows 7 for android emulator to change the landscape orientation to portrait and vic...
split string only on first instance - java
... length will be no greater than n, and the array's last entry will contain all input beyond the last matched delimiter.
The string boo:and:foo, for example, yields the following results with these parameters:
Regex Limit Result
: 2 { "boo", "and:foo" }
: 5 { "boo", "an...
Unresolved specs during Gem::Specification.reset:
...t turned out to be a missing line in the gemspec file:
$:.push File.expand_path("../lib", __FILE__)
This line is normally at the top of the file (in many of the gems I have recently been working in) and I had commented it out to see why.
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Django filter versus get for single object?
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get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're vio...
Mechanisms for tracking DB schema changes [closed]
...ed code to a production server) but we're still doing database updates manually. I would like to find or create a solution that allows us to work efficiently across servers with different environments while continuing to use Subversion as a backend through which code and DB updates are pushed aroun...
How can I clear event subscriptions in C#?
...ist, effectively.
From outside the class, you can't do this - events basically expose "subscribe" and "unsubscribe" and that's it.
It's worth being aware of what field-like events are actually doing - they're creating a variable and an event at the same time. Within the class, you end up referenci...