Databases

Company Database

- Created for use by organizations - Users access the database via computers linked to local or wide area networks.

Data Integrity

- Data integrity means the database is reliable, accurate, and aligned to the goals of the organization. - When multiple lists and data sources are maintained, information can become inconsistent leading to decreased data integrity.

Database Hierarchy

- Databases are structured in a hierarchy with characters starting at the lowest point and the database at the highest point. - This is diagram represents the hierarchy of data commonly used in databases.

Explain DBMS

A Database Management System (DBMS) maximizes the usefulness of a database. -DBMSs allow the user to create, modify, and access a database. DBMS software is comprised of five subsystems: - DBMS engine - Data definition - Data manipulation - Application administration - Data administration

Lists vs. Database

Lists work well for simplified tasks but If the task requires more structure of the data, a database may be more appropriate. - List can lead to redundancy and can't be updated

Distributed Database

The data in a database is stored in different physical locations and accessed via client/server networks.

Advantages of Databases

- Databases have many advantages when compared to other methods of managing and storing data. - Databases allow for the storage of large amounts of data efficiently and securely. - Databases enable data sharing and help to ensure data integrity. - They also allow for centralization, which is when data is maintained in only one file.

Commercial Database

- Large database that covers specific subjects - Commercial databases are also referred to as information utilities or data banks.

Multidimensional database

- Multidimensional databases organize and store information in a cube format that can be analyzed using different dimensions. - Dimensions allow the data to be analyzed from different perspectives. - Data cubes have a measure attribute and a feature attribute.

Object oriented database

- Object-oriented databases store information in objects rather than in tables. - Objects contain data and procedures for processing and working with data. - Object-oriented databases use Object Query Language to construct queries that extract data from the database.

Relational Database

- Relational databases organize data into tables based on structured data groupings. - Relational databases use links, called relationships, between tables. - Information in tables is stored in rows called records, and columns called fields.

DBMS Subsystems - Application Generation

- The application generation subsystem includes tools that create forms and reports and programming languages such as Visual Basic and Java. - Application generation subsystems include tools for creating visually appealing data entry screens and for creating easy to use data entry screens.

DBMS Subsystems - Data Administration

- The data administration subsystem allows for the management of the database. - Management features include data recovery, support, maintaining the operations of the database, and security. - In both large and small organizations these tasks are often handled by a database administrator (DBA). - DBAs are tasked with maintaining the database, assigning access rights, and interacting with and/or designing the database.

DBMS Subsystems - Data Definition

- The data definition subsystem describes the logical construction of the database using a data dictionary or data schema. - The data dictionary of a database contains descriptions of the data structure.

DBMS Subsystems - Data Manipulation

- The data manipulation subsystem allows for data maintenance and data analysis. - The data manipulation subsystem includes a data maintenance feature which permits adding, deleting, and editing data in the database. - Most database subsystems use a specific programming language called structured query language (SQL).

What's a database?

- collection of related data that can be sorted, logically organized, queried, and stored. - Buying from Amazon, created data that needs to be stored and managed - Databases are used to create a structure for data and allow processed data to be used and interpreted.

Individual Database

A combined set of data files intended to be used by one person

DBMS Subsystems - The Engine

The DBMS engine provides an interface between the logical view (front-end) and physical view (back-end) of the data. - For example, if a user requests data, such as a username or password, this is done through the logical view.