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Optimistic vs. Pessimistic locking
...database systems define terms such as SESSION setting.
Nowadays, over the Internet, we no longer execute reads and writes in the context of the same database transaction, and ACID is no longer sufficient.
For instance, consider the following use case:
Without optimistic locking, there is no way...
Type definition in object literal in TypeScript
....7
state.instance && state.instance.fun();
// Or the long winded way because the above just feels weird
if (state.instance) { state.instance.fun(); }
// Or the I came from C and can't check for nulls like they are booleans way
if (state.instance != null) { state.instanc...
When to use enumerateObjectsUsingBlock vs. for
...mes down to personal preference. For me, the idiomatic and readable option wins. In this case, that is Fast Enumeration using for-in.
Benchmark:
NSMutableArray *arr = [NSMutableArray array];
for (int i = 0; i < 100; i++) {
arr[i] = [NSString stringWithFormat:@"%d", i];
}
int i;
__block NSUI...
Yes/No message box using QMessageBox
...rk on Qt 4 and 5, requires QT += widgets on Qt 5, and CONFIG += console on Win32 to see qDebug() output.
See the StandardButton enum to get a list of buttons you can use; the function returns the button that was clicked. You can set a default button with an extra argument (Qt "chooses a suitable de...
Get value from JToken that may not exist (best practices)
...e sake of moving my code to a platform that has a better JSON parser (say, Win8 for example). So, for what I asked, yes, your code would be perfect.
– Paul Hazen
Mar 17 '12 at 23:27
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Java: how do I get a class literal from a generic type?
...methods a la Method method = clzz.getDeclaredMethod("getSomeFoo"); so much win! Thank YOU!
– Naruto Sempai
Feb 9 '17 at 2:12
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How do I “source” something in my .vimrc file?
...:set yy bbbb4dw
The only file sourced by default is the .vimrc(_vimrc on windows) so that's a place you can keep all the commands you use to set up Vim every time.
Where it gets interesting is the fact that since a sourced file is just a series of commands, and sourcing is a command, you can sour...
What should I do when 'svn cleanup' fails?
...be of interest for somebody. You can delete them recursively with the following command: rm -rf find . -type f -name lock
– H6.
Jan 20 '12 at 14:47
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Async call with await in HttpClient never returns
...a call I am making from inside a xaml-based, C# metro application on the Win8 CP; this call simply hits a web service and returns JSON data.
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Removing the remembered login and password list in SQL Server Management Studio
...rosoft\Microsoft SQL Server\100\Tools\Shell\SqlStudio.bin worked for me in Win7.
– IsmailS
Jul 22 '10 at 5:24
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