What is functional Dependency? Functional Dependency is the starting point of normalization. It exists when a relation between two attributes allow you to determine the corresponding attribute’s value uniquely. The functional dependency is also known as database dependency and defines as the relationship which occurs when one attribute in a relation uniquely determines another attribute. It is written as A->B which means B is functionally dependent on A. Explain ACID properties ACID properties are some basic rules, which has to…

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The degree of relation is a number of attribute of its relation schema. A degree of relation is also known as Cardinality it is defined as the number of occurrence of one entity which is connected to the number of occurrence of other entity. There are three degree of relation they are one-to-one(1:1), one-to-many(1:M), many-to-one(M:M). The degree of a relation in a database management system (DBMS) refers to the number of attributes or columns in a relation (table). So, the…

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The Entity is a set of attributes in a database. An entity can be a real-world object which physically exists in this world. All the entities have their attribute which in the real world considered as the characteristics of the object. For example: In the employee database of a company, the employee, department, and the designation can be considered as the entities. These entities have some characteristics which will be the attributes of the corresponding entity.

A stored procedure is a group of SQL statements that have been created and stored in the database. The stored procedure increases the reusability as here the code or the procedure is stored into the system and used again and again that makes the work easy, takes less time in processing and decreases the complexity of the system. So, if you have a code which you need to use again and again then save that code and call that code…

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What is data abstraction in DBMS? Data abstraction in DBMS is a process of hiding irrelevant details from users. Because database systems are made of complex data structures so, it makes accessible the user interaction with the database. For example: We know that most of the users prefer those systems which have a simple GUI that means no complex processing. So, to keep the user tuned and for making the access to the data easy, it is necessary to do data…

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The Relationship is defined as an association among two or more entities. There are three type of relationships in DBMS- One-To-One: Here one record of any object can be related to one record of another object. One-To-Many (many-to-one): Here one record of any object can be related to many records of other object and vice versa. Many-to-many: Here more than one records of an object can be related to n number of records of another object.

An entity type is specified as a collection of entities, having the same attributes. Entity type typically corresponds to one or several related tables in the database. A characteristic or trait which defines or uniquely identifies the entity is called entity type. For example, a student has student_id, department, and course as its characteristics. An entity type in a database management system (DBMS) refers to a category of similar entities that share common attributes. It represents a class of objects…

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DELETE command: DELETE command is used to delete rows from a table based on the condition that we provide in a WHERE clause. DELETE command delete only those rows which are specified with the WHERE clause. DELETE command can be rolled back. DELETE command maintain a log, that’s why it is slow. DELETE use row lock while performing DELETE function. TRUNCATE command: TRUNCATE command is used to remove all rows (complete data) from a table. It is similar to the…

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What are the three levels of data abstraction? Following are three levels of data abstraction: Physical level: It is the lowest level of abstraction. It describes how data are stored. Logical level: It is the next higher level of abstraction. It describes what data are stored in the database and what the relationship among those data is. View level: It is the highest level of data abstraction. It describes only part of the entire database. For example– User interacts with the system using…

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Inconsistent Not secure Data redundancy Difficult in accessing data Data isolation Data integrity Concurrent access is not possible Limited data sharing Atomicity problem The disadvantages of file processing systems include: Data Redundancy: In a file processing system, data redundancy is common because the same data may be duplicated in multiple files. This redundancy can lead to inconsistencies and increased storage requirements. Data Inconsistency: Since there is no centralized control over data in file processing systems, it’s challenging to ensure consistency…

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