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SQL join: selecting the last records in a one-to-many relationship
... purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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Precise Financial Calculation in JavaScript. What Are the Gotchas?
...avoid when using JavaScript to do this type of math—if it is possible at all!
7 Answers
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Maven: best way of linking custom external JAR to my project?
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I think you should use mvn install:install-file to populate your local repository with the library jars then you should change the scope from system to compile.
If you are starting with maven I suggest to use maven directly not IDE plugins as it adds an e...
How to round up to the nearest 10 (or 100 or X)?
...en just define:
roundUp <- function(x) 10^ceiling(log10(x))
This actually also works when x is a vector:
> roundUp(c(0.0023, 3.99, 10, 1003))
[1] 1e-02 1e+01 1e+01 1e+04
..but if you want to round to a "nice" number, you first need to define what a "nice" number is. The following lets us...
How to move screen without moving cursor in Vim?
...of the screen
(Careful with zz, if you happen to have Caps Lock on accidentally, you will save and exit vim!)
zt - move current line
to the top of the screen
zb - move
current line to the bottom of the
screen
share
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How to disable margin-collapsing?
...eft / right
position: absolute
display: inline-block / flex
You can test all of them here: http://jsfiddle.net/XB9wX/1/.
I should add that, as usual, Internet Explorer is the exception. More specifically, in IE 7 margins do not collapse when some kind of layout is specified for the parent element...
How to cancel a Task in await?
...below, and it works to some point. The CancelNotification method DOES get called, which makes you think the task was cancelled, but in the background the task keeps running, then after it's completed, the status of the Task is always completed and never cancelled. Is there a way to completely halt t...
How to set default font family for entire Android app
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@LorenzoBarbagli, you can check Calligraphy
– Brais Gabin
Jun 2 '14 at 10:23
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Do fragments really need an empty constructor?
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Yes they do.
You shouldn't really be overriding the constructor anyway. You should have a newInstance() static method defined and pass any parameters via arguments (bundle)
For example:
public static final MyFragment newInstance(int title, String messa...
Create a GUID in Java
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@angel Yes, it is theoretically possible for the UUID.randomUUID method to return a duplicate, but this is not at all a realistic concern. The Oracle/OpenJDK implementation uses a cryptographically-strong random number generator. Given that, and given ...