A database are a collection of data organized in a manner that allows access, retrieval, and use of that data. Data are a collection of unprocessed items, which can include text, numbers, images, audio and video. For example, you can type text on a keyboard, talk into a computer’s microphone, transfer photos taken with a digital camera, and capture motion and sounds with a video camera and store the recordings on a computer.
CHARACTER
A bit are the smallest unit of data that a computer can process. Eight bits grouped together in a unit comprise a byte. In the ASCII and EBCDIC coding schemes, each bytes represents a single character, which can be a number (5), letter (S), punctuation mark (?), or other symbol (&). The Unicode coding scheme, by contrast, uses one or two bytes to represent a character.
A field can be define as a combination of one or more related character or bytes and it was the smallest unit of data. It represents an attribute of some entity. An entity was a generalized class of people, place, or things for which data are collected, stored, and maintained. Examples of entity include employees, inventory, and customer. Most organizations organize and store data as entities. An attribute was a characteristic of an entity. For example employee number, last name, first name, hires date and department numbers are attributes for an employee.
RECORD
A collection of related data fields was a record. By combining description of various aspects of an object or activity is obtained. For instance, an employee record is a collection of fields about one employee. One field would be the employee’s name, another address, and still others her phone number, pay rate, earning made to date, and so forth.
FILE
A collection of related records was a file. For example an employee file was a collection of all company employee records. Likewise, an inventory file are a collection of all inventory records for a particular company or organization. PC database software often refers to files as tables.
DATABASE
At the highest level of this hierarchy was database, a collection of integrated and related files. Together bits, character, fields, records files, and database from the hierarchy of data. Characters are combined to make a field, a field are combined to make a record, records are combined to make a file, and files are combined to make a database. A database houses not only these levels of data but the relationship among them.
The evolution of data management technology: from tradition file to warehouse.
THE TRADITIONAL APPROACH VERSUS THE DATABASE APPROACH
THE TRADITIONAL APPROACH
In early day, organizations are adaptive systems with constantly changing data and information needs. For any growing or changing business, managing data can become quite complicated. One of the most basic ways to manage data are via files. Because a file are a collection of related records, all records associated with a particular application can be collected and managed together in an application specific file. At one time, most organizations had numerous application data specific file; for example, customer records often were maintained in separate files, with each file relating to a specific process completed by the company, such as shipping and billing. This approach to data management, whereby separate data files are created and stored for each application program, is called the traditional approach to data management. For each particular application, one or more data files is created
PROBLEMS WITH TRADITIONAL FILE PROCESSING
1) Data redundancy
- independent data files included a lot of duplicated data
- duplicated data: the same data were recorded and stored in several files
- this data redundancy caused problems when data had to be updated
- having data in independent files made it difficult to provide end users with information for ad hoc request that required accessing stored in several different files
- special computer programs had to be written to retrieve data from each independent file
3) Data dependence
- the organization of files, their physical locations and storage hardware, and the application software used to access those files- depended on one another
4) Lack data integrity of standardization
- data elements to be defined differently by different end users and applications
THE DATABASE APPROACH
Because of the problem, associated with the traditional approach to data management, many managers wanted a more efficient and effective means of organizing data. The result was the database approach to data management. In a database approach, a pool of related data are shared by multiple application programs. Rather than having separate data files, each application uses a collection of data that are either joined or related in the database.
Database Management System
The database approach offers significant advantages over the traditional file-based approach. For one, by controlling data redundancy, the database approach can use storage space more efficiently and increase data integrity. The database approach can also provide an organization with increased flexibility in the use of data. Because data once kept in two files is now located in the same database, it was easier to locate and request data for many types of processing. A database also offers the ability to share data and information resources. This can be a critical factor in coordinating organization wide responses across diverse functional areas of corporation. In sharing data, however, some consistency should exits among software programs.
To use the database approach to data management, additional software- a database management system (DBMS) - are required. A DBMS consists of a group of programs that can be used as an interface between a database and the user or the database and application program. Typically, this software acts as a buffer between the application program and the database itself.
DATA WAREHOUSE
A data warehouse are a database that holds business information from many sources in the enterprise, covering all aspects of the company’s processes, products, and customers. The data warehouse provides business users with a multidimensional view of the data they need to analyze business condition. A data warehouse are designed specifically to support management decision making, not to meet the needs of transaction processing system. The data warehouse provides a specialized decisions support database that managers the flow of information from existing corporate database and external source to end user decision support applications. A data warehouse stores historical data that has been extracted from operational system and external data sources. This operational and external data is “clean up” to remove inconsistencies and integrated to create a new information database that was more suitable for business analysis.
DATA MART
A data mart are a subset of a data warehouse. Data marts bring the data warehouse concept- on-line analysis of sale, inventory, and other vital business data that has been gathered from transaction processing systems- to small and medium-sized businesses and to departments within large companies. Rather than store all enterprise data in one monolithic database, data marts contain a subset of the data for single aspect of a company’s business. In fact, there may be even be more detailed data for a specific area in a data mart than what a data warehouse would provide.
Applications and Data Marts
DATA MINING
Data mining are an information analysis too that involves the automated discovery of pattern and relationship in a data warehouse. Data mining represents the next step in the evolution of decision support system. It makes use of advanced statistical technique and machine learning to discover facts in a large database, including database on the internet.
Data Mining Process
The Data mining’s objective are to extract patterns, trends, and rules from data warehouse to evaluate proposed business strategies, which in turn will improve competitiveness, improve profits, and transforms business processes.
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