chapter 5 data processing

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Chapter 5: Database Processing BUA 235

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Chapter 5: Database Processing

BUA 235

Purpose of the Database

• We covered much of this already!

• That said, a database exists to keep track of things

• We covered much of this already!

• That said, a database exists to keep track of things

Relationships

• Something else we already discussed!!!

• Keys: Primary keys and Foreign keys: establish relationships between tables, records, and related meta data….

• Remember metadata!?!

• Something else we already discussed!!!

• Keys: Primary keys and Foreign keys: establish relationships between tables, records, and related meta data….

• Remember metadata!?!

Components of a Database application system

What are the components of a database application system?

• A DBMS program is used to create, process, and administer a database.

– Popular DBMS products include:• DB2 from IBM• Access from Microsoft (for personal computers)• SQL Server from Microsoft (for large computer systems)• Oracle from Oracle Corporation• MySQL, an open-source product that’s license-free

• It’s easy to confuse a DBMS, which is a software program, with a database, which is a collection of tables, relationships and metadata. But, they are two different concepts.

• A DBMS program is used to create, process, and administer a database.

– Popular DBMS products include:• DB2 from IBM• Access from Microsoft (for personal computers)• SQL Server from Microsoft (for large computer systems)• Oracle from Oracle Corporation• MySQL, an open-source product that’s license-free

• It’s easy to confuse a DBMS, which is a software program, with a database, which is a collection of tables, relationships and metadata. But, they are two different concepts.

What are the components of a database application system?

• DBMSs are used to process databases by reading, inserting, modifying, or deleting data.

– The Structured Query Language (SQL), is an international standard language used by most major DBMS programs for processing databases.

• A DBMS includes tools to help you administer a database. You can • Set up a security system that includes permissions and passwords.• Back up the data to prevent it from being lost or compromised.• Improve the performance of applications by adding structures.• Remove data that’s no longer needed.

How do database applications make databases more useful?

• A database application includes forms, reports, queries, and applications programs available to one or more users.

• This figure shows three different applications stemming from a single

DBMS and a single database.

Enterprise DBMS vs. Personal DBMS

• Enterprise DBMS: products process large organizational and workgroup databases– These systems support many, possibly thousands

of users and many different database applications

• Personal DBMS: designed for smaller, simpler database applications – Often support fewer than 100 users, and normally

less than 15 users

• Enterprise DBMS: products process large organizational and workgroup databases– These systems support many, possibly thousands

of users and many different database applications

• Personal DBMS: designed for smaller, simpler database applications – Often support fewer than 100 users, and normally

less than 15 users

Data modeling

• This we talked about already as well!

• Data models describe the data and relationships that will be stored in the database– Very akin to a blueprint!

• Called a Entity-Relationship (E-R) Data model– Made up of entities, attributes, and an identifier (PK)

Normalization

• Is the process of converting a poorly structured table into two or more well-structured tables.

– Resolves problems with data integrity….

• Data integrity problems are serious in that they produce incorrect and inconsistent information

– Once users lose confidence in the information, the system obviously loses a considerable amount of value which translates into a burden for the organization

• Is the process of converting a poorly structured table into two or more well-structured tables.

– Resolves problems with data integrity….

• Data integrity problems are serious in that they produce incorrect and inconsistent information

– Once users lose confidence in the information, the system obviously loses a considerable amount of value which translates into a burden for the organization

What is the user's role in the development of databases?

• Your role in the database development process is to decide what data should be included and how records should relate to one another.

• The best time to change a database structure is during the data modeling stage. It’s easier and cheaper to change your mind before anything is actually built. The costs of correcting the database in time and money later on may be very high.

• Each entity must contain all the data you need to do your job.

• Each relationship must accurately reflect the appropriate view of your business.

• You must be the final judge of how well the database will serve your needs. Do not go forward until the data model is accurate.

What are the responsibilities for database administration?

• Databases are an important resource for most businesses.

• As databases touch more aspects of systems and business functions, the utility of a database increases as do potential problems.

• Database administration manages the development, operation, and maintenance of databases.

• Database administration must protect the database and maximize its availability for authorized use.

What are the responsibilities for database administration?

What are the responsibilities for database administration?

Database administration tasks are divided into four categories as shown below and on the next slide.

Continued….