Let's stop hardcoding our initial state and fetch it from the server instead. In this lesson you will learn: Set up basic data fetching Leverage the afterCreate lifecycle hook to automatically run any setup logic a model instance needs to do after cr…
Loading Data into HAWQ Leave a reply Loading data into the database is required to start using it but how? There are several approaches to achieve this basic requirement but achieve the result by approaching the problem in different ways. This allows…
How to use a PDI job to move a file into HDFS. Prerequisites In order to follow along with this how-to guide you will need the following: Hadoop Pentaho Data Integration Sample Files The sample data file needed for this guide is: File Name Content we…
A system includes a server and a controller embedded in a device. Both the server and the embedded controller are capable of communicating over a computer network. The embedded controller sends a command to the server over the computer network that i…
getDerivedStateFromProps is lifecycle hook introduced with React 16.3 and intended as a replacement for componentWillReceiveProps. It is invoked after a component is instantiated as well as when it receives new props. It should return an object to up…
getSnapshotBeforeUpdate is a lifecycle hook that was introduced with React 16.3. It is invoked right before the most recently rendered output is committed and the value returned by it will be passed as a third parameter to componentDidUpdate. It enab…
I’m going to go over some methods to import data from text files into SQL Server today. The particular file I went out and grabbed is comma delimited and with a few qualifiers in it. It is a typical file you may get and a request made to import or ju…
在localhost中准备好了一个test数据库和一个pet表: mysql> SHOW DATABASES; +--------------------+ | Database | +--------------------+ | information_schema | | test | +--------------------+ rows in set (0.01 sec) mysql> USE test Database changed mysql> SHOW TABLES;…
一.实验要求 导入数据到数据库的表里 表内容如下: name owner species sex birth death Fluffy Harold cat f 1993-02-04 Claws Gwen cat m 1994-03-17 Buffy Harold dog f 1989-05-13 Fang Benny dog m 1990-08-27 Bowser Diane dog m 1979-08-31 1995-07-29 Chirpy Gwen bird f 1…
DECLARE @BJ GEOGRAPHY DECLARE @XT GEOGRAPHY /* GET Latitude/Longitude FROM here:http://www.travelmath.com/cities/Beijing,+China the distance unit in SRID 4326 is the meter */ SELECT @BJ = geography::Point('39.92889', '116.38833', 4326) SELECT…
1. ngOnChanges is called before ngOnInit but after constructor() 2. ngOnChanges is called because of @Input() obj, obj's reference changes. If you mutate one the object's prop, it won't trigger ngOnChanges, you have to create new object.…
What could be the issue, for example we have two list: Parent component: @Component({ selector: 'passenger-dashboard', styleUrls: ['passenger-dashboard.component.scss'], template: ` <div> <passenger-count [items]="passengers"> </p…
The bcp Command-Line Utility You use the bcp (bulk copy program) tool to address the bulk movement of data. This utility is bidirectional, allowing for the movement of data into and out of a SQL Server database. bcp uses the following syntax: bcp [da…
What is AngularJS? AngularJS is a JavaScript MVC framework developed by Google that lets you build well structured, easily testable, and maintainable front-end applications. And Why Should I Use It? If you haven’t tried AngularJS yet, you’re missing…
Define a collection: var AppointmentList = Backbone.Collection.extend({model: Appointment}); RESET the json: var appointments = new AppointmentList(); var json = [ {title: 'Back pain'}, {title: 'Dry mouth'}, {title: 'Headache'} ]; appointments.reset(…
MST has a pretty unique feature: It allows you to capture private state on models, and manage this state by using lifecycle hooks. For example by setting up a WebSocket connection and disposing of the connection automatically as soon as the instance…
