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SQL: How to properly check if a record exists
...rs in recent RDBMS's optimize SELECT COUNT(*) anyway, so while there is a difference in theory (and older databases), you shouldn't notice any difference in practice.
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eclipse stuck when building workspace
...to check the Error view and/or the error log ([workspace]/.metadata/.log). If that doesn't help, you'll probably need to include more info about which plugins you have installed and which projects you have. Can you create a minimal workspace which reproduces the problem?
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Regular expression to extract text between square brackets
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\[(.*?)\]
Explanation:
\[ : [ is a meta char and needs to be escaped if you want to match it literally.
(.*?) : match everything in a non-greedy way and capture it.
\] : ] is a meta char and needs to be escaped if you want to match it literally.
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How can I interrupt a ServerSocket accept() method?
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And what to do if the connection was already accepted and the thread is waiting for some data: while((s=in.readLine()) != null) ?
– Alex Fedulov
Aug 24 '12 at 10:56
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What must I know to use GNU Screen properly? [closed]
...s use the split screen features, but certainly not daily. The other tip is if screen seems to have locked up because you hit some random key combination by accident, do both ^Q and ^A ^Q to try to unlock it.
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Where is array's length property defined?
...in the array whereas myArray.length ([]) provides the "capacity". That is, if for myArray = new int[10];, it returns 10. It is not the number of objects you've put in the array.
– wmorrison365
Feb 16 '12 at 13:15
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What does placing a @ in front of a C# variable name do? [duplicate]
...n seeing a lot of @ symbols in front of variable names. What does this signify or do?
6 Answers
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How do I get the name of captured groups in a C# Regex?
...GroupNames();
foreach (string groupName in groupNames)
if (groups[groupName].Captures.Count > 0)
namedCaptureDictionary.Add(groupName,groups[groupName].Value);
return namedCaptureDictionary;
}
}
Once this extension method is in place, you can get...
Pushing read-only GUI properties back into ViewModel
... var frameworkElement = (FrameworkElement)dependencyObject;
if ((bool)e.NewValue)
{
frameworkElement.SizeChanged += OnFrameworkElementSizeChanged;
UpdateObservedSizesForFrameworkElement(frameworkElement);
}
else
{
fra...
How to get the second column from command output?
...) is being printed. To help visualize it, this is what it would look like if we wanted to add blank spaces around $2 instead of quotation marks: '{print " "$2" "}'. We can also add format spacing to make it a little easier to grok: '{print " " $2 " "}'
– Tom
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