Tuesday, 9 February 2021

Git And Github

 Git And Github




  • Git is a Free and open 
  • version control system
  • speed and efficiency
Git hub


  • GitHub is the best place to share code with friends
Github is a website and cloud-based service that helps developers store and manage their codes.

git commnds

  • git int
  • git add
  • git status
  • git commit -m " your message"
  • git remote add origin "https...... github address"
  • git remote -v
  • git push -u origin master
  • git remote remove origin

ER Diagram

 ER Diagram

ER Diagram stands for Entity Relationship 

ERD is a diagram that displays the relationship of entity sets stored in a database. In other words, ER diagrams help to explain the logical structure of databases. ER diagrams are created based on three basic concepts: entities, attributes and relationships.


ER Diagrams contain different symbols that use rectangles to represent entities, ovals to define attributes and diamond shapes to represent relationships.


R diagram looks very similar to the flowchart. However, ER Diagram includes many specialized symbols, and its meanings make this model unique. The purpose of ER Diagram is to represent the entity framework infrastructure.

ER Model


ER Model stands for Entity Relationship Model is a high-level conceptual data model diagram. ER model helps to systematically analyses data requirements to produce a well-designed database. The ER Model represents real-world entities and the relationships between them. Creating an ER Model in DBMS is considered as a best practice before implementing your database.



ER Diagram Symbol

  • Rectangles: This Entity Relationship Diagram symbol represents entity types
  • Ellipses : Symbol represent attributes
  • Diamonds: This symbol represents relationship types
  • Lines: It links attributes to entity types and entity types with other relationship types
  • Primary key: attributes are underlined
  • Double Ellipses: Represent multi-valued attributes
ER Diagram Symbols

Components of the ER Diagram

  • Entities
  • Attributes
  • Relationships
Usages of ER Diagram
  • ER model allows you to draw Database Design
  • It is an easy to use graphical tool for modeling data
  • Widely used in Database Design
  • It is a GUI representation of the logical structure of a Database
  • It helps you to identifies the entities which exist in a system and the relationships between those entities

Monday, 8 February 2021

Mongo DB

 Mongo DB



  • Mogo db is a document-oriented database program
  • Mongodb easy to learn and use
  • it's store data in flexible
  • Mongodb is free to use

usage of Mongodb 

  • Save big data
  •  Content Management and delivery
  • Mobile and Social infrastructure
  • User Data Management

Features of Mongodb
  • High availability through built-in replication and failover
  • Horizontal scalability
  • End-to-end security
  • Native document validation
  • Schema less
  • Ease to scale-out
  • No complex joins


Mongo db commands

sudo mongo:-To start the server
sudo mongod:- To start the client

use "database-name":- Create a database if any database has on this name this command select that data base.

show dbs:- Shows all database

Note:-Atleast 1 file must be inside the database to show the database  

db.createCollection"name":-To create a Collection

db."collectionname".drop():-To delete a Collection

db.dropDatabase():-Delete The database

db."collectionname".insert:-To insert the document to the collection

db."collectionname".remove:-Remove Collection

db."collectionname".find:-To show the document inside the Collection


$gt:-Greater than
$gte:-Greater than or Equal
$lt:-Less than
$lte:-Less than Equal
$eq:- Equal
$ne:-Not Equal

JQuery

 JQuery(write less,do more)




  • This is not a language 
  • It's javascript library
  • Easy to learn
  • Jquery makes for easier to use javascript on our web
  • Open source

JQuery is not a only library for javascript But JQuery is probably most popular and extendable

JQuery works mostly All browers



                        JQuery library has some features
  1. HTML/DOM manipulation
  2. CSS manipulation
  3. HTML event methods
  4. Effects and animations
  5. AJAX
  6. Utilities
JQuery Syntax

  • Basic syntax is:-  $(selector).action()
  •  $ sign to define/access jQuery
  • (selector) to "query (or find)" HTML elements
  • A jQuery action() to be performed on the elements(s)

Two ways to insert the jquery

Download the jQuery library from jQuery.com

1.There are two versions of jQuery available for downloading:
    • Production version - this is for your live website because it has been minified and compressed
    • Development version - this is for testing and development (uncompressed and readable code)

2.Include jQuery from a CDN, like Google

   <head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
</head>






JavaScript

 Java Script




  • Java script is a programming language
  • It's makes our Web pages interactive
  • Interpreted Language
  • Java script mostly using in client side
  • Object based language
  • scripting language 
  • Easy to learn
                                Javascript is not a java completely different and they are
                                                             2 languages 

Why Study JavaScript?

JavaScript is one of the 3 languages all web developers must learn:

   1. HTML to define the content of web pages

   2. CSS to specify the layout of web pages

   3. JavaScript to program the behavior of web pages



Java script fundamentals

  • Variables
  • Arrays
  • Loops
  • Conditions
  • Comparison&operators
  • Objects
  • functions
  • Program flow
  • Data Types
  • Prototypes
  • Events
Usages of Javascript
  • Responsive
  • Interactive
  • Create Cookies
  • Detect user
  • Form Validation
  • Create animations
  • Build apps
  • Slideshow
You can change html attribute value ans css style by javascript

 import javascript
In HTML, JavaScript code is inserted between <script> and </script> tags.


JavaScript Display Possibilities

JavaScript can "display" data in different ways:

  • Writing into an HTML element, using innerHTML.
  • Writing into the HTML output using document.write().
  • Writing into an alert box, using window.alert().
  • Writing into the browser console, using console.log().

Bootstrap

 Bootstrap



  • Bootstrap 4 is latest version of bootstrap 
  • Bootstrap is a css frame work that most popular
  • mobile approachable framework
  • Responsive framework 
  • it's totally free
  • Free to modify,save,share and use in our project 
  • All major browsers are supported but internet Explorer 9 and down isn't supported 
Bootstrap Components
  • Album
  • Pricing
  • Checkout
  • Cover
  • Carousel
  • Sign-in 
  • Sticky Footer
  • Blog
  • Dashboard
  • Sticky Footer navbar
Frame Works
  • Template
  • Grid
  • Cheatsheet
  • Cheatssheet rtl
Two Methodes to import Bootstrap
  1. Include Bootstrap 4 from a CDN
  2. Download Bootstrap 4 from getbootstrap.com

Containers

You learned from the previous chapter that Bootstrap requires a containing element to wrap site contents.

Containers are used to pad the content inside of them, and there are two container classes available:

  1. The .container class provides a responsive fixed width container
  2. The .container-fluid class provides a full width container, spanning the entire width of the viewport

Bootstrap 4 Grid System

Bootstrap's grid system is built with flexbox and allows up to 12 columns across the page.

If you do not want to use all 12 columns individually, you can group the columns together to create wider columns:

span 1span 1span 1span 1span 1span 1span 1span 1span 1span 1span 1span 1
 span 4 span 4 span 4
span 4span 8
span 6span 6
span 12

Cascading Style Sheets

 Css

CSS stands for Cascading Style Sheets.css describes how html elements are to be displayed on screen, paper, or in other media.Css saves a lot of work. It can control the layout of multiple web pages all at once.


Css has 3 types

1.Inline:-Add a style line by Line(directly in html)

2.Internal:-Add style in body

3.External:-Linking external css file


Css Syntax



ex:-p {

  text-align: center;}

p is a selector

text-align is a property, and center is the property value

Css selectors

CSS selectors are used to "find" the HTML elements you want to style.

  • Simple selectors:-
 Selects HTML elements based on the element name
The id attribute of an HTML element to select a specific element.
  • Combinator selectors 
(select elements based on a specific relationship between them)
  •  class selectors(select elements based on a certain state)
The id selector uses the id attribute of an HTML element to select a specific element.
  • Pseudo element selectors (select and style a part of an element)
html tags selected by html element
  • Attribute selector (select elements based on an attribute or attribute value)
The Attribute selector uses the  attribute of an HTML element to select a specific element.