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Why are ToLookup and GroupBy different?
...table with a billion rows in it?
The billion rows are sent over the wire, and you build the lookup table locally.
What happens when you call GroupBy on such an object?
A query object is built; end of story.
When that query object is enumerated then the analysis of the table is done on the databa...
How to determine the current shell I'm working on
...t to actual shell name in csh or tcsh
$ZSH_NAME is set on zsh
ksh has $PS3 and $PS4 set, whereas the normal Bourne shell (sh) only has $PS1 and $PS2 set. This generally seems like the hardest to distinguish - the only difference in the entire set of environment variables between sh and ksh we have i...
How to disable right-click context-menu in JavaScript [duplicate]
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Capture the onContextMenu event, and return false in the event handler.
You can also capture the click event and check which mouse button fired the event with event.button, in some browsers anyway.
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How to filter Android logcat by application? [duplicate]
How can I filter Android logcat output by application? I need this because when I attach a device, I can't find the output I want due to spam from other processes.
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Creating an Android trial application that expires after a fixed time period
... run the app save the date/time to a file, database, or shared preferences and every time you run the app after that check to see if the trial period has ended. This is easy to circumvent because uninstalling and reinstalling will allow the user to have another trial period.
The second approach is...
HashSet vs. List performance
...be better off using a List<T>.
I did a test for this on my machine, and, well, it has to be very very small to get an advantage from List<T>. For a list of short strings, the advantage went away after size 5, for objects after size 20.
1 item LIST strs time: 617ms
1 item HASHSET strs t...
Why does int num = Integer.getInteger(“123”) throw NullPointerException?
... variation of this problem was featured in Return of the Puzzlers: Schlock and Awe (TS-5186), Josh Bloch and Neal Gafter's 2009 JavaOne Technical Session presentation. Here's the concluding slide:
The Moral
Strange and terrible methods lurk in libraries
Some have innocuous soundi...
examining history of deleted file
If I delete a file in Subversion, how can I look at it's history and contents? If I try to do svn cat or svn log on a nonexistent file, it complains that the file doesn't exist.
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Sass combining parent using ampersand (&) with type selectors
...t to .item a.item for some reason. I tried doing a#{&} on it's own too and still same result.
– jaminroe
Nov 11 '15 at 16:54
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Selenium wait until document is ready
...completely? I want something generic, I know I can configure WebDriverWait and call something like 'find' to make it wait but I don't go that far. I just need to test that the page loads successfully and move on to next page to test.
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