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How do I manage MongoDB connections in a Node.js web application?
...database errors when using the connection anyway, this doesn't lead to any extra inline handling.
– java-addict301
Jun 6 '17 at 0:31
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Reference alias (calculated in SELECT) in WHERE clause
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I needed some extra conditionals in a MERGE statement, and this was the only way I could make it work. Thanks!
– Eric Burdo
Jul 11 '19 at 17:44
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How can I find out if I have Xcode commandline tools installed?
...ow you get it from the store, and with this new mechanism it can't install extra things outside of the Xcode.app, so you have to manually do it yourself, by:
xcode-select --install
On Xcode 4.x you can check to see if they are installed from within the Xcode
UI:
On Xcode 5.x it is now here:
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Using [UIColor colorWithRed:green:blue:alpha:] doesn't work with UITableView seperatorColor?
...(from http://github.com/Jon889/JPGeneral)
//.h file
@interface UIColor (JPExtras)
+ (UIColor *)colorWithR:(CGFloat)red G:(CGFloat)green B:(CGFloat)blue A:(CGFloat)alpha;
@end
//.m file
@implementation UIColor (JPExtras)
+ (UIColor *)colorWithR:(CGFloat)red G:(CGFloat)green B:(CGFloat)blue A:(CGFlo...
Add a common Legend for combined ggplots
...88
group4 -0.072626 0.104988",header=TRUE)
library(ggplot2)
library(gridExtra)
p1 <- ggplot(df1, aes(x=x, y=y,colour=group)) + geom_point(position=position_jitter(w=0.04,h=0.02),size=1.8) + theme(legend.position="bottom")
p2 <- ggplot(df2, aes(x=x, y=y,colour=group)) + geom_point(position...
How do I enumerate the properties of a JavaScript object? [duplicate]
...hat might modify a prototype) doesn't break yours. Apart from adding a few extra bytes of code, there is no downside to using hasOwnProperty().
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Maintain aspect ratio of div but fill screen width and height in CSS?
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To avoid using extra markup here you can add an element using ::before or ::after and give that element a height of 0 and a padding-bottom relative to the objects width and 0 width of its own. That will have the same effect but with less ma...
What is “overhead”?
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Overhead typically reffers to the amount of extra resources (memory, processor, time, etc.) that different programming algorithms take.
For example, the overhead of inserting into a balanced Binary Tree could be much larger than the same insert into a simple Linked Li...
Rotating a two-dimensional array in Python
... list, we will need to put list() around that to convert it. With a couple extra list() calls to convert the iterators to an actual list. So:
rotated = list(reversed(list(zip(*original))))
We can simplify that a bit by using the "Martian smiley" slice rather than reversed()... then we don't need th...
Exposing database IDs - security risk?
...n't use unpredictable IDs at all. Bugs happen, so unpredictable IDs are an extra safety mechanism. Besides, access control is not the only reason to use them: predictable IDs can reveal sensitive information such as the number of new customers within a certain timeframe. You really don't want to exp...