IML PRELIMS

• Data - raw facts

• Data - building blocks of information

• Information - Not raw facts

• Information - Processed data

• Information - used to reveal the meaning of data

• Good decision making - High chance to succeed

• Database - Data that resides in the base

• End User Data, Meta Data - two things inside the database

  • Meta data - data about data

  • End User Data - names
    
    # hinde kumplete here, sorry :(((

DMS - Database Management System

• used to communicate to data

• used to manage data

• to restrict some data

Types of Database

• Single User - 1 at a time, Desktop Database

• Multi User - 2 or more, Workgroup, Enterprise

• Data Location - Centralized or Distributed

  • Centralized - placed in a single unit

  • Distributed - supports data across several units

• Operational Database - day to day transaction

• Data Warehouse - where data lives

• Extensive Markup Language - XML meaning

  • used for manipulation index form

Database Design

• Many components

• Requirements Gathering - need to meet requirement

• Conceptual Design - ERD

• Logical Design - increment

• Physical Design - all is applied to DMS

• Normalization - organized. avoids redundancy

• Inducing - used index to have faster data retrieval

• Security

Basic File terminol;

SQL

• Structured Query Language - meaning of SQL

  • SQL - Computer language aimed to store, manipulate, and query data stored in relational databases.

  • 1974 - SQL first appeared in this year

  • SQL statements - Most of the actions you need to perform on a database are done with _____________

  • SQL statements - consist of keywords that are easy to understand.

  • Case insensitive.

SQL DATA TYPES

• Numeric

  • Integer

  • Float

  • Real

  • Numeric

  • Decimal

• Character String

  • CHAR(n)

  • VARCHAR(n)

• Date/Datetime

• Binary

  • Blob

  • Binary

  • Raw
    

• SQL RELATIONAL OPERATORS

  • =

  • <> or !=

  • > or >=

  • < or <=
    

• SQL LOGICAL OPERATORS

  • AND

  • IN

  • NOT

  • OR

  • LIKE

  • BETWEEN

  • ALL

  • ANY

  • EXISTS

  • SOME

• DATA DEFINITION LANGUAGE - DDL meaning

  • DDL - It consists of SQL commands that can be used to define the database schema.

  • DDL - It simply deals with descriptions of the database schema and is used to create and modify the structure of database objects in the database.

EXAMPLES OF DDL COMMANDS

• CREATE - Create database or its objects (table, index, function, views, store, procedure, and triggers)

• DROP - Deletes objects from the database

• ALTER - Alter the structure of the database

• TRUNCATE - Remove all records from a table, including all spaces allocated for the records are removed

• COMMENT - Add comments to the data dictionary

• RENAME - Rename an object existing in the database

• DATA MANIPULATION LANGUAGE - DML meaning

  • SQL commands that deal with the manipulation of data present in the database belong to DML or Data Manipulation Language and this includes most of the

    SQL statements.

EXAMPLES OF DML COMMANDS

• SELECT - It is used to retrieve data from the database

• INSERT - Insert data into a table

• UPDATE - Update existing data within a table

• DELETE - Delete records from a database table

SQL COMMANDS: https://www.w3schools.com/sql/default.asp