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Can you have if-then-else logic in SQL? [duplicate]
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106
You can make the following sql query
IF ((SELECT COUNT(*) FROM table1 WHERE project = 1) > ...
Show/hide 'div' using JavaScript
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440
How to show or hide an element:
In order to show or hide an element, manipulate the element's s...
Simultaneously merge multiple data.frames in a list
....frame(i = c("c","d","a"), l = 7:9, stringsAsFactors=FALSE)
Update June 2018: I divided the answer in three sections representing three different ways to perform the merge. You probably want to use the purrr way if you are already using the tidyverse packages. For comparison purposes below, you'll...
Stretch background image css?
...nd-size: cover;
}
Works in:
Safari 3+
Chrome Whatever+
IE 9+
Opera 10+ (Opera 9.5 supported background-size but not the keywords)
Firefox 3.6+ (Firefox 4 supports non-vendor prefixed version)
In addition you can try this for an IE solution
filter: progid:DXImageTransform.Microsoft.AlphaIma...
Eclipse Workspaces: What for and why?
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edited Jun 20 at 9:12
Community♦
111 silver badge
answered Dec 23 '14 at 20:47
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Is it good practice to NULL a pointer after deleting it?
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Setting a pointer to 0 (which is "null" in standard C++, the NULL define from C is somewhat different) avoids crashes on double deletes.
Consider the following:
Foo* foo = 0; // Sets the pointer to 0 (C++ NULL)
delete foo; // Won't do anything
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reference assignment is atomic so why is Interlocked.Exchange(ref Object, Object) needed?
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answered Feb 3 '10 at 16:20
Eric LippertEric Lippert
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How to implement classic sorting algorithms in modern C++?
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+50
Algorithmic building blocks
We begin by assembling the algorithmic building blocks from the Standard Library:
#include <algorithm...
Converting A String To Hexadecimal In Java
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200
Here's a short way to convert it to hex:
public String toHex(String arg) {
return String.f...
CSS background image to fit width, height should auto-scale in proportion
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