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Quickly reading very large tables as dataframes
... MonetDB.R gives you a data type that pretends to be a data frame but is really a MonetDB underneath, increasing performance. Import data with its monetdb.read.csv function. dplyr allows you to work directly with data stored in several types of database.
Storing data in binary formats can also be...
Does use of final keyword in Java improve the performance?
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Usually not. For virtual methods, HotSpot keeps track of whether the method has actually been overridden, and is able to perform optimizations such as inlining on the assumption that a method hasn't been overridden - until it lo...
Using node.js as a simple web server
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Simplest Node.js server is just:
$ npm install http-server -g
Now you can run a server via the following commands:
$ cd MyApp
$ http-server
If you're using NPM 5.2.0 or newer, you can use http-server without installing it with npx. This isn't recommended for u...
What is the difference between require() and library()?
...uld add this:
It is probably best to avoid using require() unless you actually will be using the value it returns e.g in some error checking loop such as given by thierry.
In most other cases it is better to use library(), because this will give an error message at package loading time if the pack...
Automatic HTTPS connection/redirect with node.js/express
...ng to get HTTPS set up with a node.js project I'm working on. I've essentially followed the node.js documentation for this example:
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How to len(generator()) [duplicate]
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Generators have no length, they aren't collections after all.
Generators are functions with a internal state (and fancy syntax). You can repeatedly call them to get a sequence of values, so you can use them in loop. But they don't contain any elements, so asking for the length of ...
SLF4J: Failed to load class “org.slf4j.impl.StaticLoggerBinder”. error
...lipse, instead of it's embedded maven.
That is done in three steps:
1 Install maven on local machine (the test-machine was Ubuntu 10.10)
mvn --version
Apache Maven 2.2.1 (rdebian-4) Java version: 1.6.0_20 Java home:
/usr/lib/jvm/java-6-openjdk/jre Default locale: de_DE, platform
encoding: UTF-8 OS...
JSON.NET Error Self referencing loop detected for type
I tried to serialize POCO class that was automatically generated from Entity Data Model .edmx and when I used
25 Answers
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LEFT JOIN vs. LEFT OUTER JOIN in SQL Server
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Absolutely correct. OUTER is allowed for ANSI-92 compatibility.
– Sean Reilly
Jan 2 '09 at 21:34
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LINQ to SQL Left Outer Join
... how this crazy syntax works? I fail to see how any of those keywords magically makes it a left join. What does the "into sr" do? Linq frustrates me sometimes :)
– Joe Phillips
Apr 7 '14 at 21:29
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