History Of The File Management System Information Technology Essay

History Of The File Management System Information Technology Essay Its the first management system introduced in 1960s. This was actually the proof of concept, in which the feasibility of storing large amount of data was shown. Its the management system in which all data is stored on a single large file as indicated from its name. It just contains data in which there are no relationships and no links between data and records. Its main drawback is searching a record or data takes a lot of time. Also these systems had a lot of drawbacks like for updating or to modify the data we have to do a lot of efforts as searching took time. Sorting the records was one of time taking process. Courtesy of http://en.kioskea.net/contents/bdd/bddtypes.php3Hierarchical Database System: 1970s 1990s In order to take account of the disadvantages in the previous file management system, this data base system was introduces a new concept of parent-child relationship between the flat files (like trees concept). The origin of data is called root have several branches coming out of it at different levels and the last level is called leaf. For example a parent can have many children but a child can only have a parent (1: M relation). This model uses pointers for navigation between stored data. For accessing the data we have to follow the hierarchy from top to bottom. Its main drawback is that if we need to modify or wants to add something in the data we have to alter all the structure thats again a very tedious task. Some times our data can best model if we have multiple parents/owners, so hierarchical Database system restricts ourselves in doing so. Network Database System: 1970s 1990s Courtesy of http://en.kioskea.net/contents/bdd/bddtypes.php3Some database can be best modeled by having multiple parents per child. So many-to-many relations were introduced in which a record can have multiple owners (M: M). Examples are DMS and IDMS. Its the more flexible than hierarchical database system as it reduces redundancy. Its drawbacks are:    ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Maintainability (for changing the relationships we may require physical reformation of data),  ·Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Lack of strength. Any failure in the system leaves the dangling reference to the data which can somehow be recovered   As there is no limit on relationships so our system becomes more complex. Courtesy of http://en.kioskea.net/contents/bdd/bddtypes.php3 Relational Database System: 1980s present (second generation DBMS) In order to overcome the drawbacks in the previous systems, this Database system was introduced in which data is organized in tables as shown (each record shown in a row and attributes shown in the columns). Its structure, i.e., a table, is easily understood and the design and standardization process is well defined. So the relationships formed between the tables. Its the flexible, well-established system. Due to its sound theoretical base this database system is used from many years. Standard data access language through SQL( SQL is limited when accessing complex data) SQL considered the fourth generation language. This system dont support for complex data types. Courtesy of http://en.wikipedia.org/wiki/Object_databaseObject-Oriented Database Management System: 1990s present (third generation database system) During 1990s unstructured data become more common so in order to handle these increasing complex data, object-oriented database system were introduced. Its a model in which information is represented in the form of objects as used in object-oriented programming. Object databases should not be used when there would be few join tables and there are large volumes of data. Object-oriented data base management system gives high performance to manage objects and give ease to the complex connection of objects. This makes it so much reliable than any other data base management systems. This is one of the database management systems that supports the creation of data as objects. This includes some kind of support for classes of objects and the inheritance of class properties and methods by subclasses and their objects. Today, object oriented databases plays important role in enterprises develop systems and infrastructure to deal with more complex data requirements. OBJECT-RELATIONAL (1990s-present): Its the same as relational data base but using the concepts of object-oriented data bases that are classes, inheritance and concept of objects. It can be described as mid-way between relational data base and object-oriented data base. In this DBMS the approach is same as that of relational DBMS. There are some features of an object-relational data base management system that includes SQL that can be used to create both relational and objects. It also supports to different functions of object-oriented. DATA-WAREHOUSING (1980s-present): Its the collection of data which helps management in decision making. . Its basic concept is to provide architectural model for the flow of data. In large organizations there are multiple tasks assign to different groups of persons each having their records. The warehouse includes development of systems to extract data from their operating systems plus provides managers flexible access to the data. It focuses on modeling and analysis of data for decision makers. Excludes data not useful in decision support process. Data once recorded cannot be updated. Data warehouse requires two operations in data accessing i.e. initial loading of data, access of data. The benefit of the data ware house is that it gives same data regardless of the source that is easier to analyze information. Another benefit is that if the source system data is washed out the information in the data ware house which is under control can be stored safely. WEB-ENABLED (1990s-present): The dramatically effect on database environment is the ascendance of the internet thats why its called web-enabled data base system. Web-enabled data base is simply a data base which is web-based interface. The main purpose of web-enabled allows users to access data from central warehouse. The application of web-enabled data base is ticketing of an airline or buying computer direct from manufacturer through internet. All of this needs data base and easy connection if multiple users are through internet. Example of web-enabled data baseIn 2000s the most common change in data base environment is addition of XML defined web services. It is found everywhere for business purposes. Summary of Database Application: Courtesy of Modern Database Management 8th edition by JEFFREY A. HOFFER