Mcqs for dbs 621 ca2 database 621 ca 2 300 mcqs entity. An overview of database management system, database system vs file system, characteristics of database approach, dbms. Generalization generalization is the process of extracting common properties from a set of entities and create a generalized. Dbms aggregation with dbms overview, dbms vs files system, dbms architecture, three schema architecture, dbms language, dbms keys, dbms generalization, dbms specialization, relational model concept, sql introduction, advantage of sql, dbms normalization, functional dependency, dbms. A major aim of relational database design is to group attributes into relations so as to minimize information redundancy and thereby reduce the file storage space required by the base.
Dbms specialization and generalization watch more videos at lecture by. Its more like superclass and subclass system, but the only difference is the approach. Dbms specialization in hindi hindi tutorials point. Generalization, specialization and aggregation in er model. If your rdbms supports it, id use an enum for the role column mysql, e. Database normalization is a technique of organizing the data in the database. This newly formed entity is called generalized entity. For example, pigeon, house sparrow, crow and dove can all be generalized as birds. Generalization is the reverse process of specialization. Explain weak entity set, specialization, generalization.
Weipang yang, information management, ndhu unit 11 file organization and access methods 1112 indexing. Constraints on specialization generalization participation constraint determines whether every member in superclass must participate as a member of one of the subclasses. In generalization, the higher level entity can also combine with. Begg, database systems a practical approach to design, implementation. Shared characteristics can be attributes, associations, or methods. In generalization, the sub entities are combined together into a super entity set on the basis of some common. Relational database design by er and eerrto relational. Covers topics like features of eer model, sub class, super class, specialization, generalization. Categories dbms tags aggregation in dbms pdf, aggregation in dbms tutorialspoint, association in dbms, difference between specialization and generalization in dbms in hindi, generalization and specialization in software engineering, generalization in dbms in hindi, generalization in javatpoint, generalization kya hai, generalization. Relational database design by er and eertorelational. The xml technology specifies the syntax for writing wellformed documents.
Suppose find all suppliers in city xxx is an important query. Categories dbms in hindi tags database 12 comments post navigation. Dbms generalization with dbms overview, dbms vs files system, dbms. Database management system dbms tutorial database management system or dbms in short, refers to the technology of storing and retriving users data with utmost efficiency along with safety and security features. In specialization, a group of entities is divided into subgroups based on their characteristics. As we know icici bank po recruitment programme has become a regular recruitment event with an intake 2 or 3 batches. Single relation with multiple type attributes proceed as in the previous approach, except. Relational database systems 1 ifis tu braunschweig. Generalization specialization aggregation in dbms pdf september 7, 2019 posted by admin generalization, specialization and aggregation in er model generalizationgeneralization is a process of generalizing. Enhanced entity relationship model tutorial to learn eer model in simple, easy and step by step way with examples and notes. Specialization in dbms extended er feature youtube. Generalization and specialization both the terms are more common in object oriented technology, and they are also used in the database with the same features. Study 125 terms computer science flashcards quizlet.
In generalization, a number of entities are brought together into one generalized entity based on their similar characteristics. Generalization, specialization and aggregation concepts in dbms. Hierarchies specialization and generalization are main principles of. Dbms allows its users to create their own databases which are relevant with the nature of work they want. Participation constraint o weak entity type, exid relationship types, generalization and specialization o some extensions.
Dbms functional dependency with dbms overview, dbms vs files system, dbms architecture, three schema architecture, dbms language, dbms keys, dbms generalization, dbms specialization, relational model concept, sql introduction, advantage of sql, dbms normalization, functional dependency, dbms. Specialization is a process in which an entity is divided into subentities. Generalization is a bottomup approach in which two lower level entities combine to form a higher level entity. Generalization, specialization and aggregation in er model are used for data abstraction in which abstraction mechanism is used to hide details of a set of objects. Generalization is the term that we use to denote abstraction of common properties into a base class in uml. Data base management system generalization and specialization are important relationships that exist betweena higher level entity set and one or more lower level entity sets. Generalization is a process in which the common attributes of more than one entities form a new entity. Difference between generalization and inheritance with. Generalization occurs when we ignore the differences and acknowledge the similarities between lower entities or child classes or relations tables in dbms to form a higher entity. How to implement and insert value sql specialization. W generalization and specialization diagrammatic notation sometimes used to distinguish between generalization and specialization arrow pointing to the generalized superclass represents a generalization arrows pointing to the specialized subclasses represent a specialization. Here you can download the free lecture notes of database management system pdf notes. For each regular strong entity type e in the er schema, create a relation r that includes all the simple.
Describe the concepts of specializationgeneralization, aggregation and composition. Generalization specialization specialization is a process, which is opposite to generalization. Database management system pdf notes bca 2019 all tricks. In generalization, the difference and similarities between lower entities are ignored to form higher entity whereas in specialization a higher entity is split to form lower entities. In generalization, the higher level entity can also combine with other lower level entities to make further higher level entity. There are many files in the database management system, and all the files are inter related. Categories dbms tags difference between specialization and generalization in dbms in hindi, generalization in dbms in hindi, generalization in javatpoint, generalization kya hai, generalization or specialization pdf, generalization tutorialspoint, how specialization is different from generalization, what is generalization.
You generally have the right idea or, at least, one of the common idioms to implement such a database schema. The concept of generalization specialization is associated with special types of entities known as superclasses and subclasses, and the process of attribute inheritance. Constraints on specialization generalization participation. You can think of it as a reverse process of generalization, in generalization two entities combine together to form a new higher level entity. Specialization and generalization hierarchies and lattices specialization hierarchy every subclass participates as a subclass in only one classsubclass relationship results in a tree structure or strict hierarchy specialization. Generalization is the process of extracting shared characteristics from two or more classes, and combining them into a generalized superclass. Difference between generalization and specialization in. Generalization occurs when we ignore the differences and acknowledge the similarities between lower entities or child classes or relations tables in dbms. Dbms language, dbms keys, dbms generalization, dbms specialization. This video explain extended features of er model specialization. When we implement generalization in a programming language, it is called inheritance. Database schema design using entityrelationship approach.
If the specialization is already attributedefined it uses that as t, otherwise t is a new attribute. Dbms specialization with dbms overview, dbms vs files system, dbms. Similarly, in a school database, persons can be specialized as teacher, student, or a staff, based on what role specjalization play in school as entities. For an example, pigeon, house sparrow, crow and dove all can be generalized as birds. Specialization specialization is the opposite of generalization. Normalization is a systematic approach of decomposing tables to eliminate data redundancy repetition and. Dbms generalization in hindi hindi tutorials point. Difference between generalization and specialization in dbms.
Consider representation of specialization and generalization. Mcqs for dbs 621 ca2 database 621 ca 2 300 mcqs entity relationship modelling topic 4 1 in enhancedentityrelationship collection of entities in form. As mentioned above, the process of generalizing entities, where the generalized entities contain the properties of all the generalized entities, is called generalization. Generalization generalization is the process of extracting common properties from a set of entities and create a generalized entity from it. Generalization and specialization are very important concepts in dbms. The key difference between generalization and specialization in dbms is that generalization is the process of combining lower level entities to produce the higherlevel.
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