Database Language A Database Management System has all the required interfaces and languages for the purpose of expressing the updates and queries in the database. These database languages can be used for reasons like storing, reading, and updating the data in the database. There are a number of database languages which can be used. These … Read more
Three Schema Architecture The three-schema architecture is commonly known as the three-tier architecture or ANSI/SPARC architecture. These terms and framework are for describing a particular database system structure. The physical database and the user applications are kept separate using this three-tier architecture. This type of architecture has three, which are what keeps the user and … Read more
GENERALIZATION Generalization resembles the bottom-up way where two or more entities of minor level combine in order to form a greater level entity only if they possess any attributes that are common amongst them. The entities of higher level are capable of combining with the minor level entities in order to develop into a major … Read more
SPECIALIZATION Specialization is considered as a top-down access, which is just the opposite of Generalization. According to the specialty, any higher level entity has the potential to get classified further into two minor level entities. It is also implemented in order to find the subset of any entity set which shares some different characteristics. Firstly, … Read more
According to aggregation, the relation between any two entities is considered as a single entity. Any relationship with its respective entities is aggregated in a higher level entity. For instance, Any course entity is offered by the center entity as a single entity in the corresponding relationship with any other entity visitor. According to … Read more
ER MODEL The ER model is a high-level data model which stands for the Entity-Relationship Model. The ER Model is used for defining the relationship and elements for any specific system. The ER model or the structure of the database is represented as a diagram known as the entity-relationship diagram. It based on a conceptual … Read more
The number of occurrences in one entity, which is correlated with the times of events in another entity defines the degree of relationship. There is a three degree of relationship: One-to-one (1:1) One-to-many (1: M) Many-to-many (M: N) 1. One-to-one According to the One-to-one relationship, anyone occurrence in the entity is related to exclusively one … Read more
The databases are represented by the notations, and the following notations are reduced to the collection of tables. In the databases, every relationship or entity set can be denoted in the tabular forms. This is the ER diagram: There are various points for the conversion of the ER diagram to the table: The respective Entity … Read more
Understanding Keys in Relational Database Keys are an integral element of Relational database model. These are used in identifying and establishing relationships between tables. Moreover, keys are necessary in recognizing any row of data or record in a table. These can either be a group of aspects or a single aspect wherein the combination … Read more
An instance of the database is the data stored in a particular database for a limited time. The storage is for the finite interval of time. When we talk about the overall design of the database, then it is called a schema. It is the skeleton structure of the database, which represents the logical … Read more