GowsiTamil CSE Notes

  Queue ADT Handwritten Notes- Click Here A  Queue  is a linear data structure in which elements are inserted at one end and removed from the other end.( Insertion → Rear,  Deletion → Front )                                   ↓ FRONT                                 ↓ REAR A B C D E    A queue follows the FIFO (First In, First Out) principle. This means that the element inserted first is removed first. A  Queue can be implemented using: Array Linked List Basic  Queue  Operations: 1. Enqueue - used to insert  a new element into the queue. 2. Dequeue - used to remove an element from the queue. 3. Peek - used to view the first element without removing it. 4. isEmpty - checks whether the queue contains any elements. 5...

  Stack ADT Handwritten Notes- Click Here A Stack is a linear data structure in which insertion and deletion of elements are performed only at one end. This end is called the TOP . Stack follows the LIFO (Last In, First Out) principle. It means the element inserted last will be removed first. A stack can be implemented using: Array Linked List Basic Stack Operations: 1. Push - used to insert a new element into the stack. 2. Pop - used  to remove an element from the stack. 3. Peek - used to view the element at the TOP without removing it. 4. isEmpty - checks whether the stack contains any elements. 5. isFull - checks whether the stack   has reached its maximum capacity Push() Operation The process of inserting a new element at the TOP of the stack is called Push . Algorithm Check whether the stack is full. If the stack is full, report Stack Overflow . Otherwise, increment TOP. Insert the new element at the TOP position.  Bef...

             Data Models Handwritten Notes- Click Here A Data Model defines how data is organized, stored, related, and accessed in a database. Types of Data Models in DBMS Hierarchical Data Model Network Data Model Relational Data Model Entity-Relationship (ER) Model Object-Oriented Data Model Object-Relational Data Model 1. Hierarchical Data Model   The Hierarchical Data Model organizes data in the form of a tree structure . Each child record has only one parent record . A parent record can have multiple child records . It mainly represents a one-to-many relationship . Data retrieval is very fast in the hierarchical model.                                   Company                   |            Department             /      ...

Enhanced Entity-Relationship(EER) Model Handwritten Notes - Click Here The Enhanced Entity-Relationship (EER) Model is an extended form of the traditional Entity-Relationship (ER) Model . The basic ER model is useful for representing entities, attributes, and relationships . However, some real-world database applications contain more complex structures such as different types of entities, inheritance, and hierarchical relationships. The EER model adds additional concepts to the ER model so that these complex requirements can be represented more clearly. The important concepts of the EER Model include: Superclass and Subclass Specialization Generalization Inheritance Disjoint and Overlapping Constraints Total and Partial Specialization Aggregation 1. Superclass and Subclass A superclass is a higher-level entity that contains common attributes shared by different entities. A subclass is a lower-level entity that contains attributes specific to that particular entity. A subcla...

Entity-Relationship(ER) Model Handwritten Notes - Click Here The Entity-Relationship (ER) Model is a conceptual data model. It helps database designers understand the requirements of a system before creating the actual database tables . It describes the important objects in a system, their properties , and the relationships between them. The three basic concepts of the ER model are Entity Attribute Relationship Entity An entity can be any real-world object, person, place, or class about which we want to store information in a database. In a traditional ER diagram, an entity is represented by a rectangle .                        Example: Employee and Department An employee works for a department. Here, Employee and Department are entities , and Works For is the relationship between them. Weak Entity A weak entity is an entity that depends on another entity for its identification of existence. A weak entity is represen...