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What is an index in SQL?
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"The index can also be a UNIQUE index..." Just to confirm with you, does that means index can al be Non-UNIQUE? I always thought its UNIQUE. I'm quite new to SQL, pardon me
– Daniel Kurniadi
May 16 at 5:01
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How is pattern matching in Scala implemented at the bytecode level?
...atterns like or patterns and combinations like "case Foo(45, x)", but generally those are just logical extensions of what I just described. Patterns can also have guards, which are additional constraints on the predicates. There are also cases where the compiler can optimize pattern matching, e.g...
Class.forName() vs ClassLoader.loadClass() - which to use for dynamic loading? [duplicate]
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I found this out the hard way, and can assuredly confirm that this is the case using Catalina. I had called getClassLoader().loadClass("..."); on a Class type to attempt to load a Torque peer class in order to run a static initializer block which maps the peer to a database...
Cleaning `Inf` values from an R dataframe
...orks, but changes all negative values in the dataset to positive! You can confirm with this:
data(iris)
#The last line here is bad - it converts all negative values to positive
iris %>%
mutate_if(is.numeric, ~scale(.)) %>%
mutate(infinities = Sepal.Length / 0) %>%
mutate_if(is.nume...
asp.net mvc: why is Html.CheckBox generating an additional hidden input
...n field. That is how ASP.NET MVC handles checkbox values.
If you want to confirm that, place a checkbox on form not with Html.Hidden, but with <input type="checkbox" name="MyTestCheckboxValue"></input>. Leave checkbox unchecked, submit form and look at posted request values on server s...
Configure apache to listen on port other than 80
...b;
Kill it with: taskkill /pid NUMBER /f (/f forces it);
Recheck resmon to confirm that the port is free now and repeat step 6.
This ensures that Apache's service was started properly, the configuration on virtual hosts config file as sarul mentioned (e.g.: C:\wamp\bin\apache\apache2.4.9\conf\extr...
Is it possible to embed animated GIFs in PDFs?
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I can confirm that embedding a MOV file in a PDF via InDesign works. But Quicktime on my iMac refuses to open GIF files. Can you give more details about that part... what version of Quicktime are you using?
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Navigation Drawer (Google+ vs. YouTube)
...here.
Edit #2:
Roman Nurik (an Android design engineer at Google) has confirmed that the recommended behavior is to not move the Action Bar when opening the drawer (like the YouTube app). See this Google+ post.
Edit #1:
I answered this question a while ago, but I'm back to re-emphasize that...
What is RemoteSystemsTempFiles in Eclipse?
...red for the first time in my workspace just after Eclipse requested (and I confirmed) the upload of user data that it does from time to time in order to improve Eclipse. I'm running Indigo.
– Carl
May 8 '12 at 0:43
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How to change Elasticsearch max memory size
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I can confirm this works for aws ami instance (installed with RPM), but first set MAX_LOCKED_MEMORY=unlimited in /etc/sysconfig/elasticsearch and bootstrap.memory_lock: true in /etc/elasticsearch/elasticsearch.yml
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