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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracle, all three methods are the same.
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Chrome DevTools Devices does not detect device when plugged in
...s://developers.google.com/chrome-developer-tools/docs/remote-debugging
Install Windows USB driver http://developer.samsung.com/android/tools-sdks/Samsung-Android-USB-Driver-for-Windows
Install Android SDK http://developer.android.com/sdk/index.html
Install Android SDK Platform-tools http://developer...
Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...ocking 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 reducing thread switch...
How to wrap async function calls into a sync function in Node.js or Javascript?
...pose you maintain a library that exposes a function getData . Your users call it to get actual data:
var output = getData();
Under the hood data is saved in a file so you implemented getData using Node.js built-in fs.readFileSync . It's obvious both getData and fs.readFileSync are sync ...
How does a Java HashMap handle different objects with the same hash code?
...ng bucket, and then it will compare the key that you gave with the keys of all pairs in the bucket, by comparing them with equals().
Now you can see how this is very efficient for looking up key-value pairs in a map: by the hash code of the key the hashmap immediately knows in which bucket to look,...
How to check if a String contains only ASCII?
The call Character.isLetter(c) returns true if the character is a letter. But is there a way to quickly find if a String only contains the base characters of ASCII?
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What is meant by “managed” vs “unmanaged” resources in .NET?
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The term "unmanaged resource" is usually used to describe something not directly under the control of the garbage collector. For example, if you open a connection to a database server this will use resources on the server (for maintaining the connection) and po...
Parsing CSV files in C#, with header
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Let a library handle all the nitty-gritty details for you! :-)
Check out FileHelpers and stay DRY - Don't Repeat Yourself - no need to re-invent the wheel a gazillionth time....
You basically just need to define that shape of your data - the fi...
Is there a version control system for database structure changes?
...keeps track of your current db version.
To migrate up, you run a command called "db:migrate" which looks at your version and applies the needed scripts. You can migrate down in a similar way.
The migration scripts themselves are kept in a version control system -- whenever you change the database ...
How to discard local changes in an SVN checkout?
...er changes are not required : """Rest of the changes I made, were for basically debugging, and are no longer required.""" :)
– Cédric Julien
Feb 27 '12 at 10:54
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