L4 Database Management System(DBMS)

4 types of DBMS

1: Hierarchical 2: Network 3: Relational 4: Object Oriented DBMS

Define Organizational Database System

1: Support several users simultaneously. 2: Include more than one application. 3: Involve multiple computers 4: Are complex in design 5: Have many tables 6: Have many databases

SQL to create and populate tables

CREATE TABLE Actors( Name CHAR(30) DateofBirth CHAR(20) ) INSERT INTO Actors VALUES('Tom Hanks',...)

Examples of Desktop DBMS products

Microsoft Access

Searching/Querying/Updating-Find all movies by 'Coppola'

Select title From Movies, Directors, Movie_Directors Where Directors.lname = 'Coppola' and Movies.mid = Movie_Directors.mid and Movie_Directors.id = Directors.id

Relational DBMS

relation of form of tables: have predefined data types. EX: MySql Oracle, Microsoft SQL Server.

Object Oriented Relation DBMS

storage of new data types: the data to be stored in form of objects, methods to do with the data.

Network DBMS

supports many-to many relationship.

Define a database Applications

1: A database application is a set of one or more computer programs that serves as an intermediary between the user and the DBMS.

Transactions have the ACID Properties:

A=Atomicity C= Consistency I= Isolation D= Durability

Hierarchical

Employs the parent child relationship of storing data. Structure of nodes represent records, Branches representing fields. EX: Windows registry configuration settings set up as tree structures with nodes.

Durability

Once a transaction has been committed, it will remain so, even in the event of power loss, crashes, or errors.

Atomicity

Requires that each transaction be "all or nothing": if one part of the transaction fails, then the entire transaction fails, and the database state is left unchanged.

Give an Example of databases:

1: Accounts database 2: Payroll database 3: Amazon's product database 5: Airline reservation database

Database Functionality are?

1: Create/store large datasets 2: Search/query/update 3: Change the structure 4: Concurrent access to many users 5: Recover from crashes 6: Security( not here, but in other apps)

Possible database Organizations

1: Files 2: Spreadsheets 3: DBMS

Define a desktop database systems

1: Have one application. 2: Have only a few tables. 3: Are simple in design 4: Involve only one computer. 5: Support one user at a time.

Data Redundancy

1: Inconsistency in data format. 2: the same information may be kept in several different place(files). 3: Data inconsistency which means various copies of the same data are conflicting; waste storage space and duplication of efforts.

Example Organizational DBMS Products

1: MySQL 2: Oracle's Oracle 3: Microsoft's SQL Server 4: IBM's DB2 5: Intersystems Cache

Define the characteristics of a Database Management System(DBMS)

1: Serves an an intermediary between database applications and the database. 2: The DBMS manages and controls database activities. 3: The DBMS creates, processes and administers the databases it controls.

What does a user of a database system do

1: Use a database application to track things. 2: Use forms to enter, read, delete and query data. 3: Produce repots.

What are the four components of a database system?

1: Users 2: Database Application 3: Database Management System(DBMS) 4:Database

What defines a database?

1: a database is a self-describing collection of related records. 2: Self-describing: A database itself contains the definition of its structure. 3:Metadata: is data describing the structure of the database data. 4: Tables within a relational database are related to each other.

What does a Database Application do?

1: create and process forms. 2: Process user queries 3: Create and Process reports 4: Execute application logic 5: Control database applications

What is a database?

A collection of files storing related data.

Data Isolation

applications cannot access data associated with other applications

Database Management System(DBMS)

is a collection of programs that enables users to create, maintain database and control all the access to the database. *The primary goal of the DBMS is to provide an environment that is both convenient and efficient for user to retrive and store information.