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Storing time-series data, relational or non?
... description, the actual PK is (Device, Metric, DateTime). (Please don't call it TimeStamp, that means something else, but that is a minor issue.) The uniqueness of the row is identified by:
(Device, Metric, DateTime)
The Id column does nothing, it is totally and completely redundant.
A...
Why does struct alignment depend on whether a field type is primitive or user-defined?
... The documentation of StructLayoutAttribute is pretty interesting. Basically, only blittable types are controlled through StructLayout in managed memory. Interesting, never knew that.
– Michael Stum♦
Jul 15 '14 at 7:01
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How do I remove duplicate items from an array in Perl?
...is as demonstrated in perlfaq4:
sub uniq {
my %seen;
grep !$seen{$_}++, @_;
}
my @array = qw(one two three two three);
my @filtered = uniq(@array);
print "@filtered\n";
Outputs:
one two three
If you want to use a module, try the uniq function from List::MoreUtils
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Capturing touches on a subview outside the frame of its superview using hitTest:withEvent:
My problem: I have a superview EditView that takes up basically the entire application frame, and a subview MenuView which takes up only the bottom ~20%, and then MenuView contains its own subview ButtonView which actually resides outside of MenuView 's bounds (something like this: Button...
How can I generate Unix timestamps?
... BSD date supports also +%s. Probably universal, as date is normally defined in POSIX.2.
– Dereckson
Nov 5 '17 at 15:41
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How to get the anchor from the URL using jQuery?
...xOf() and .substring(), like this:
var url = "www.aaa.com/task1/1.3.html#a_1";
var hash = url.substring(url.indexOf("#")+1);
You can give it a try here, if it may not have a # in it, do an if(url.indexOf("#") != -1) check like this:
var url = "www.aaa.com/task1/1.3.html#a_1", idx = url.indexOf("...
What is the size of ActionBar in pixels?
...king in android version 2.3, but "R.attr.actionBarSize" is working android all version. just use "R.attr.actionBarSize" instead of "android.R.attr.actionBarSize" and etc.
– Nathaniel Jobs
May 20 '16 at 3:23
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What is the purpose of Rank2Types?
I am not really proficient in Haskell, so this might be a very easy question.
6 Answers
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Android Studio installation on Windows 7 fails, no JDK found
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Adding a system variable JDK_HOME with value c:\Program Files\Java\jdk1.7.0_21\ worked for me. The latest Java release can be downloaded here.
Additionally, make sure the variable JAVA_HOME is also set with the above location.
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How can I use a local image as the base image with a dockerfile?
...ockerfile.
I just realised that I've been using FROM with indexed images all along.
4 Answers
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