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LISTAGG in Oracle to return distinct values

... 19c and later: select listagg(distinct the_column, ',') within group (order by the_column) from the_table 18c and earlier: select listagg(the_column, ',') within group (order by the_column) from ( select distinct the_colum...
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Are arrays in PHP copied as value or as reference to new variables, and when passed to functions?

...e copying. Use the reference operator to copy an array by reference. And the given example : <?php $arr1 = array(2, 3); $arr2 = $arr1; $arr2[] = 4; // $arr2 is changed, // $arr1 is still array(2, 3) $arr3 = &$arr1; $arr3[] = 4; // now $arr1 and $arr3 are the same ?> ...
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“Could not find any information for class named ViewController”

...roject. Steps: In the project file explorer (left panel) find the class and right click -> Delete Remove reference (do not move to trash as you will lose the class for good) Right click on the folder that contained the class -> Add files to ... Find the class you just deleted in the file sy...
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Global and local variables in R

I am a newbie for R, and I am quite confused with the usage of local and global variables in R. 3 Answers ...
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Use tab to indent in textarea

... } }); jQuery: How to capture the TAB keypress within a Textbox How to handle <tab> in textarea? http://jsfiddle.net/jz6J5/ share | improve this answer | follow ...
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How to perform .Max() on a property of all objects in a collection and return the object with maximu

...rating through the data, remembering the maximum element we've seen so far and the maximum value it produced under the projection. In your case you'd do something like: var item = items.MaxBy(x => x.Height); This is better (IMO) than any of the solutions presented here other than Mehrdad's se...
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Rotating and spacing axis labels in ggplot2

... In the newest version of ggplot2 the command would be: q + theme(axis.text.x=element_text(angle = -90, hjust = 0)) – rnorberg Sep 28 '12 at 13:18 ...
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How to complete a git clone for a big project on an unstable connection?

...codebase, but at the moment I have an internet connection of about 300kbps and it's just anything but stable. I can get the connection back any moment, but then the git clone process already stopped working, and no way to get it running again. Is there some way to have a more failure-resistant git c...
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bash: mkvirtualenv: command not found

...erage the chance that virtualenvwrapper.sh is already in your shell's PATH and just issue a source `which virtualenvwrapper.sh` share | improve this answer | follow ...
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Python != operation vs “is not”

... == is an equality test. It checks whether the right hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.) is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls ...