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Dbms slide share.pptx

  1. DATABASE MANAGEMENT SYSTEM DBMS uses the internet services to communicate reports, queries and distribute other information throughout the accounting system. The process of computerized accounting system uses databases to store and retrieve data in the form of inter-related data tables.
  2. EVOLUTION • The first wave consisted of network, hierarchical, inverted list, and (in the 1990’s) object-oriented DBMSs; it took place from roughly 1960 to 1999. • The relational wave introduced all of the SQL products (and a few non-SQL) around 1990 and began to lose users around 2008. • The decision support wave introduced Online Analytical Processing (OLAP) and specialized DBMSs around 1990, and is still in full force today. • The graph wave began with The Semantic Web stack from the Worldwide Web Consortium in 1999, with property graphs appearing around 2008 • The NoSQL wave includes big data and much more; it began in 2008.
  3. FILESYSTEMTODATABASE  A File Management system is a DBMS that allows access to single files or tables at a time. In a File System, data is directly stored in set of files. It contains flat files that have no relation to other files (when only one table is stored in single file, then this file is known as flat file).
  4. ENTITY RELATIONSHIP MODEL  An Entity-Relationship Model represents the structure of the database with the help of a diagram. ER Modelling is a systematic process to design a database as it would require you to analyze all data requirements before implementing your database.
  5. BASIC CONCEPT OF ERM Q-What is entity? A-An entity in DBMS (Database management System) is a real-world thing or a real-world object which is distinguishable from other objects in the real world. For example, a car is an entity. An attribute of an entity gives us information about the characteristic features of an entity.  ENTITY TYPE:-  Tangible Entity : Entities that exist in the real world physically. Example: Person, car, etc.  Intangible Entity : Entities that exist only logically and have no physical existence. Example: Bank Account, etc.  An entity set is a logical container for instances of an entity type and instances of any type derived from that entity type.  An entity key is a property or a set of properties of an entity type that are used to determine identity.
  6. Types of Attributes in DBMS There are different types of attributes in DBMS: Simple attributes Composite attributes Single Valued attributes Multi-Valued attributes Stored attributes Derived attributes Key attributes
  7. RELATION IN DBMS  Database relationships are associations between tables that are created using join statements to retrieve data. The following table describes the database relationships. Both tables can have only one record on each side of the relationship. Each primary key value relates to none or only one record in the related table.  A relationship set is a set of relationships of the same type. Formally it is a mathematical relation on (possibly non-distinct) sets. where is a relationship. For example, consider the two entity sets customer and account.  There are three different types of degree of relationships, they are as follows − • Unary relationship • Binary relationship • Ternary relationship
  8. TYPES OF RELATIONSHIP  One to One relationship  One to many or many to one relationship  Many to many relationships CARDINALITY cardinality usually represents the relationship between the data in two different tables tables by highlighting how many times a specific entity occurs in comparison to another. For example, the database of an auto repair shop may show that a mechanic works with multiple customers every day.
  9. Relational Data Model  A relational data model involves the use of data tables that collect groups of elements into relations. These models work based on the idea that each table setup will include a primary key or identifier. Other tables use that identifier to provide "relational" data links and results. Database administrators use something called Structured Query Language (SQL) to retrieve data elements from a relational database.
  10. PhaseofdataModelling  There are three stages of data modeling: conceptual, logical, and physical. Conceptual data models focus on the general structure of the system, the entities to be included, the business requirements of the database to be built, and the types of data to be stored.
  11. THREE SCHEMA COMPONENTS  Three-schema architecture is an idea in relational database design that breaks a database down into three different categories according to its use and structure, and to the roles played by system administrators, designers and end users.