Tutorial by Examples: a

1. Jenkins : Jenkins is an open source continuous integration tool written in Java. The project was forked from Hudson after a dispute with Oracle. In a nutshell, Jenkins is the leading open source automation server. Built with Java, it provides hundreds of plugins to support building, testing, de...

Setup Spark context in R To start working with Sparks distributed dataframes, you must connect your R program with an existing Spark Cluster. library(SparkR) sc <- sparkR.init() # connection to Spark context sqlContext <- sparkRSQL.init(sc) # connection to SQL context Here are infos how...

What: Caching can optimize computation in Spark. Caching stores data in memory and is a special case of persistence. Here is explained what happens when you cache an RDD in Spark. Why: Basically, caching saves an interim partial result - usually after transformations - of your original data. So, ...

SQL Server 2012 In Transact SQL , you may define an object as Date (or DateTime) using the [DATEFROMPARTS][1] (or [DATETIMEFROMPARTS][1]) function like following: DECLARE @myDate DATE=DATEFROMPARTS(1988,11,28) DECLARE @someMoment DATETIME=DATEFROMPARTS(1988,11,28,10,30,50,123) The parameter...

If you'd like to quickly test if an ability class is giving the correct permissions, you can initialize an ability in the console or on another context with the rails environment loaded, just pass an user instance to test against: test_ability = Ability.new(User.first) test_ability.can?(:show, Pos...

A UserForm is a class module with a designer and a default instance. The designer can be accessed by pressing Shift+F7 while viewing the code-behind, and the code-behind can be accessed by pressing F7 while viewing the designer. Work with a new instance every time. Being a class module, a form i...

The QueryClose event is raised whenever a form is about to be closed, whether it's via user action or programmatically. The CloseMode parameter contains a VbQueryClose enum value that indicates how the form was closed: ConstantDescriptionValuevbFormControlMenuForm is closing in response to user act...

import groovy.json.JsonSlurper; def jsonSlurper = new JsonSlurper() def obj = jsonSlurper.parseText('{ "foo": "bar", "baz": [1] }') assert obj.foo == 'bar' assert obj.baz == [1]

import groovy.json.JsonSlurper; def jsonSlurper = new JsonSlurper() File fl = new File('/path/to/fils.json') // parse(File file) method is available since 2.2.0 def obj = jsonSlurper.parse(fl) // for versions < 2.2.0 it's possible to use def old = jsonSlurper.parse(fl.text)

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' In addition to maps, lists and primitives groovy.json.JsonOutput also supports a POJOs serialitzation: import groovy.json.JsonOutput; ...

import groovy.json.JsonOutput; def json = JsonOutput.toJson([foo: 'bar', baz: [1]]) assert json == '{"foo":"bar","baz":[1]}' def pretty = JsonOutput.prettyPrint(json) assert pretty == '''{ "foo": "bar", "baz": [ ...

$true and $false are two variables that represent logical TRUE and FALSE. Note that you have to specify the dollar sign as the first character (which is different from C#). $boolExpr = "abc".Length -eq 3 # length of "abc" is 3, hence $boolExpr will be True if($boolExpr -eq $tr...

Here are simplified steps (based on the official documentation) required to create a Firebase project and connect it with an Android app. Add Firebase to your app Create a Firebase project in the Firebase console and click Create New Project. Click Add Firebase to your Android app and fol...

From dataframe: mtrdd <- createDataFrame(sqlContext, mtcars) From csv: For csv's, you need to add the csv package to the environment before initiating the Spark context: Sys.setenv('SPARKR_SUBMIT_ARGS'='"--packages" "com.databricks:spark-csv_2.10:1.4.0" "sparkr-shel...

Installation via Composer The easiest way to install the Incubator is by using Composer. Install Composer and create a new composer.json file in the root of your project. |-- app |-- public | `-- index.php |-- vendor |-- composer.json Add the following content to the composer.json file. ...

Loading the Incubator into your project Add the following lines of code to your loader file $loader = new Phalcon\Loader(); $loader->registerNamespaces([ 'Phalcon' => '/path/to/your/vendor/phalcon/incubator/Library/Phalcon/', // any other namespaces you have loaded // ... ...

This is an example of a simple GET API call wrapped in a promise to take advantage of its asynchronous functionality. var get = function(path) { return new Promise(function(resolve, reject) { let request = new XMLHttpRequest(); request.open('GET', path); request.onload = resolve; ...

SQL Server 2008 R2 SET TRANSACTION ISOLATION LEVEL READ COMMITTED This isolation level is the 2nd most permissive. It prevents dirty reads. The behavior of READ COMMITTED depends on the setting of the READ_COMMITTED_SNAPSHOT: If set to OFF (the default setting) the transaction uses shared l...

Dirty reads (or uncommitted reads) are reads of rows which are being modified by an open transaction. This behavior can be replicated by using 2 separate queries: one to open a transaction and write some data to a table without committing, the other to select the data to be written (but not yet com...

Use list() to quick assign a list of variable values into an array. See also compact() // Assigns to $a, $b and $c the values of their respective array elements in $array with keys numbered from zero list($a, $b, $c) = $array; With PHP 7.1 (currently in beta) you will be able to use s...