database management system approach .pptx

Database Management System approach and data models

1. dbms approach

2. DBMS DBMS stands for Database Management System DBMS is a software used provide interface between user and database. DBMS provides different components with SQL as Database Access Language. Ex: Oracle, DB2, SQL Server, MySQL, etc

3. Types of approaches There are mainly two approaches to designing a DBMS : Relational approach Object-oriented approach

4. Relational Approach It is the most widely used approach to design DBMS It is based on the relational data model In relational Model data represented in the form of tables Table consisting of rows and columns The relationships between the tables are defined by using keys. SQL is the most common language used to interact with relational databases

5. Object-oriented approach It is based on the object-oriented data model In this model data represented in the form of Objects Objects are organized into classes relationships between the classes are defined by using inheritance. Object-oriented databases are typically used in applications where complex data structures and Relations involved.

6. Advantages of DBMS Data sharing: In DBMS, the authorized users of an organization can share the data among multiple users. Easily Maintenance: It can be easily maintainable due to the centralized nature of the database system. Backup : It provides backup and recovery subsystems which create automatic backup of data from hardware and software failures and restores the data if required. multiple user interface: It provides different types of user interfaces like graphical user interfaces, application program interfaces

7. Data Security: DBMS provides features such as user authentication, authorization, and access control, which help to secure data from unauthorized access, modification, or deletion . Data Integrity: DBMS enforces data integrity constraints to ensure that the data is accurate and consistent. Data Consistency : DBMS ensures that the data stored in database is consistent, even if multiple users access and modify same data simultaneously.

8. Data Models

9. What is Data Model? the logical design and structure of a database  defines how data will be stored, accessed and updated in a DBMS While the  Relational Model  is the most widely used database model ,

10. Types of Data Models Database Evolution changes the style of data stored in database. There are five different data models Hierarchical Data model Network Data Model Entity relationship data model Relational data model Object Oriented

11. Hierarchical Model organizes data into a tree-like-structure (upside down tree) Hierarchy starts with single root expands like a tree, adding child nodes to the parent nodes . In this model child node will only have a single parent node.

12. Advantages are . It promotes data sharing. Maintains parent child relationship Database security is provided and enforced by DBMS Provides data integrity. It is efficient with one to many relationships. Disadvantages are . Requires knowledge of physical data storage Requires knowledge of hierarchical path Changes of structures will require changes in all applications No support of DDL or DML

13. Network model It is extension of the Hierarchical model . data is organized more like a graph One child can have multiple parent nodes Data has more relationships established in this model Used for many to many data relationships Most widely used model before Relational model introduced.

14. Advantages are . It promotes data sharing. Maintains parent child relationship Database security is provided and enforced by DBMS Provides data integrity. It is efficient with many to many relationships. Disadvantages are . Requires knowledge of physical data storage Requires knowledge of hierarchical path Changes of structures will require changes in all applications