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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...mbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_node/sort-invocatio...
Listing each branch and its last revision's date in Git
I need to delete old and unmaintained branches from our remote repository. I'm trying to find a way with which to list the remote branches by their last modified date, and I can't.
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Is mathematics necessary for programming? [closed]
...al knowledge from high school or fresh year college math, no more no less, and that almost all of programming tasks can be achieved without even need for advanced math. He argued, however, that algorithms are fundamental & must-have asset for programmers.
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How to strip all non-alphabetic characters from string in SQL Server?
...t dbo.RemoveNonAlphaCharacters('abc1234def5678ghi90jkl')
Once you understand the code, you should see that it is relatively simple to change it to remove other characters, too. You could even make this dynamic enough to pass in your search pattern.
Hope it helps.
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How to sleep for five seconds in a batch file/cmd [duplicate]
...ds, such as taking an image being displayed by the webcam. (Run the script and smile at the camera, for example.)
30 Answer...
Examples of Algorithms which has O(1), O(n log n) and O(log n) complexities
What are some algorithms which we use daily that has O(1), O(n log n) and O(log n) complexities?
11 Answers
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Test if characters are in a string
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@GregSnow -- Tried system.time(a <- grepl("abc", vec)) and system.time(a <- grepl("abc", vec, fixed=TRUE)), and fixed=TRUE is still, if anything slightly slower. The difference isn't appreciable with these short strings, but fixed=TRUE still doesn't seem to be faster. Thanks ...
Underscore: sortBy() based on multiple attributes
...atient[0].roomNumber;
}).value();
When the second sortBy finds that John and Lisa have the same room number it will keep them in the order it found them, which the first sortBy set to "Lisa, John".
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Hibernate, @SequenceGenerator and allocationSize
...nce by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
6 Answers...