Different Types of Dbms and Dbms Models Essay Example
A database can be a set of flat files stored on computer tape or disk or it could consist of database tables that are managed by a Database Management System (DBMS).
There are different types of DBMS products: relational, network and hierarchical, multidimensional, object. The most widely commonly used type of DBMS today is the Relational Database Management Systems (RDBMS).
Database management systems (DBMS) are designed to use one of five database structures to provide simplistic access to information stored in databases. The five database structures are: the hierarchical model, the network model, the relational model, the multidimensional model, and the object model.
Inverted lists and other methods are also used. A given database management system may provide one or more of the five models. The optimal structure depends on the natural organization of the application's data, and on the application's requirements, which include transaction rate (speed), reliability, maintainability, scalability, and cost.
Hierarchical Model
The hierarchical data model organizes data in a tree structure. There is a hierarchy of parent and child data segments. This structure implies that a record can have repeating information, generally in the child data segments. Data in a series of records, which have a set of field values attached to it. It collects all the instances of a specific record together as a record type. These record types are the equivalent of tables in the relational model, and with the individual records being the equivalent of rows. To create links between these record types, the hierarchical model uses Parent Child Relationships. These are a 1:N mapping between record types. This is done by using trees, like set theory used in the relational model, "borrowed" from maths. For example, an organization might store information about an employee, such as name, employee number, department, salary. The organization might also store information about an
There are different types of DBMS products: relational, network and hierarchical, multidimensional, object. The most widely commonly used type of DBMS today is the Relational Database Management Systems (RDBMS).
Database management systems (DBMS) are designed to use one of five database structures to provide simplistic access to information stored in databases. The five database structures are: the hierarchical model, the network model, the relational model, the multidimensional model, and the object model.
Inverted lists and other methods are also used. A given database management system may provide one or more of the five models. The optimal structure depends on the natural organization of the application's data, and on the application's requirements, which include transaction rate (speed), reliability, maintainability, scalability, and cost.
Hierarchical Model
The hierarchical data model organizes data in a tree structure. There is a hierarchy of parent and child data segments. This structure implies that a record can have repeating information, generally in the child data segments. Data in a series of records, which have a set of field values attached to it. It collects all the instances of a specific record together as a record type. These record types are the equivalent of tables in the relational model, and with the individual records being the equivalent of rows. To create links between these record types, the hierarchical model uses Parent Child Relationships. These are a 1:N mapping between record types. This is done by using trees, like set theory used in the relational model, "borrowed" from maths. For example, an organization might store information about an employee, such as name, employee number, department, salary. The organization might also store information about an