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select * vs select column
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It always pulls a tuple (except in cases where the table has been vertically segmented - broken up into columns pieces), so, to answer the question you asked, it doesn't matter from a performance perspective. However, for ma...
How can I create tests in Android Studio?
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This answer is for people who are just getting started with Android testing. I will provide two simple examples to help you see how testing works. If you follow along for the next 10 minutes, you will be all set up to start adding your tests to your own app. I think you'll be surp...
Do checkbox inputs only post data if they're checked?
Is it standard behaviour for browsers to only send the checkbox input value data if it is checked upon form submission?
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What is the difference between string primitives and String objects in JavaScript?
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JavaScript has two main type categories, primivites and objects.
var s = 'test';
var ss = new String('test');
The single quote/double quote patterns are identical in terms of functionality. That aside, the behaviour you are trying to name is called auto-boxing. So what...
Why are preprocessor macros evil and what are the alternatives?
...ved a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alternative after so many years?
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How to recursively delete an entire directory with PowerShell 2.0?
What is the simplest way to forcefully delete a directory and all its subdirectories in PowerShell? I am using PowerShell V2 in Windows 7.
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How to sort a dataframe by multiple column(s)
I want to sort a data.frame by multiple columns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
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Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...antage of nonblocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducin...
The transaction log for the database is full
...uire lots of space for the log file, I created a second log file and made it huge. Once the project is complete we then removed the extra log file.
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Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
I have an issue with my HAXM installation. Here is the thing. I got this error every single time I tried to install HAXM for my computer:
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