Semantic Web

Introduction
Semantic means the study of meaning in language. It is the study of interpretation of signs or symbols, which are used in agents or communities within same or different contexts.
In French language word has its origins in Greek “semantikos” means “significant”.

Web means a complex network of fine threads constructed by a spider, or WWW (World Wide Web (W3)) is a system connected with different server systems that support specially formatted documents. These documents are in HTML (Hypertext markup language) which links to other document including audio, video and different graphics. There are metadata, which gives describes other data. Continue reading “Semantic Web”

Flashback Database

Introduction to Flashback Technology
Flashback provides a simple, powerful and completely non-disruptive mechanism for recovering from human errors.It is used when logical corruption occurs in Oracle Database and data needs to be recovered quickly and easily.
This is applicable at Database, Table and Transaction Level.
With this technology you can diagnose, how errors are introduced in database and then repair the damage. There are different flashback technologies like Flashback Database,Flashback Drop, Flashback Table, Flashback Query, Flashback Version Query,Flashback Data Archive, Flashback Transaction Query. Almost all above mentioned technology uses the undo data for historical data other than Flashback Database and Flashback Drop, which uses Flashback logs and Recycle bin respectively. Continue reading “Flashback Database”

Angular Component Life cycle Hooks

Earlier in angular 1, we had using (ng-init), (ng-change) directives to access page initialization, change event of controller. This feature will expand in angular 2 and come up as lifecycle hooks with different phases.

So first we will know what are a Lifecycle hooks?
Lifecycle hooks are simply sequentially functions that called for specific phase of component’s life in our angular apps.

According to angular documentations lifecycle hooks are:
Angular creates it, renders it, creates and renders its children, checks it when its data-bound properties change, and destroys it before removing it from the DOM. Continue reading “Angular Component Life cycle Hooks”