In the field of database management systems (DBMS), a candidate key is a set of one or more columns that can uniquely identify a row within a table. A candidate key is also known as a "unique identifier" or "primary key." In this article, we will discuss the importance of candidate keys in DBMS and how they are used to maintain the integrity and consistency of a database. What is a Candidate Key? A candidate key is a set of one or more columns that can be used to uniquely identify a row within a table. In other words, no ... Read More

Introduction In a database management system (DBMS), the scheduler is responsible for managing the execution of concurrent transactions. The scheduler uses a schedule, which is a sequence of actions that the DBMS must execute, to ensure that the system remains in a consistent state and that concurrent transactions do not interfere with each other. There are two types of schedules: serial schedules and non-serial schedules. In this article, we will discuss the calculation of both types of schedules in a DBMS. Serial Schedules A serial schedule is a schedule in which all transactions are executed one after another, without any ... Read More

Introduction A data model is a blueprint that represents the organization of data and the relationships between different data entities. It is an essential component of any software system as it defines how data is stored, accessed, and modified. In this article, we will explore the building blocks of a data model and how they work together to form a cohesive whole. Data Entities The first building block of a data model is data entities, which represent the objects or concepts that are relevant to the system. For example, in an e-commerce system, data entities might include products, customers, orders, ... Read More

A data warehouse is a central repository of integrated data that is used for reporting and analysis. It stores large amounts of historical and current data and enables fast query performance for analytical purposes. A data warehouse can be used to support business decision-making, improve operational efficiency, and gain a competitive edge. In this article, we will discuss the process of building a data warehouse from scratch. Understanding the Requirements for a Data Warehouse Before starting the design and construction of a data warehouse, it is important to understand the business requirements and the type of data that will be ... Read More

Data was previously stored in relational data management systems when Hadoop and big data concepts were not available. After introducing Big Data concepts, it was essential to store the data more concisely and efficiently. However all data stored in the related data management system needs to be transferred to the Hadoop archive. With Sqoop, we can transfer this amount of personal data. Sqoop transfers data from a related database management system to a Hadoop server. Thus, it facilitates the transfer of large volumes of data from one source to another. Here are the basic features of Sqoop − Sqoop ... Read More

Most SQL databases are relational. Relational Databases are tabular and have a pre-determined schema that organizes the data logically. Database management solutions have evolved from the classic relational paradigm to the more flexible and scalable NoSQL approach.Some say NoSQL stands for "non-SQL, " but many refer to it as SQL. NoSQL is a non-relational database management system for certain data models. These data models don't need a schema and are scalable. It offers a system-supported alternative to relational databases' tabular format for storing and retrieving data. NoSQL databases don't require a certain schema. You can store data without worrying about ... Read More

PL/SQL is a combination of SQL along with the procedural features of programming languagesFLOYD’s triangle − it is a triangle formed by natural numbers. It is the triangle formed by filling numbers in rows starting from 1 at the top-left corner. It is a right-angled triangle i.e. the count of numbers in each row is the same as the row number.In this problem, we are given a natural number N. Our task is to create Floyd’s triangle in PL/SQL.Let’s take an example to understand the problemInput: 16 Output: 1 2 3 4 5 6 7 8 9 10 11 12 ... Read More

In this problem, we are given a number N. Our task is to finding sum of first n natural numbers in PL/SQL.PL/SQL is a combination of SQL along with the procedural features of programming languages.PL/SQL has the following features −PL/SQL is tightly integrated with SQL.It offers extensive error checking.It offers numerous data types.It offers a variety of programming structures.It supports structured programming through functions and procedures.It supports object-oriented programming.It supports the development of web applications and server pages.PL/SQL has the following advantages −SQL is the standard database language and PL/SQL is strongly integrated with SQL. PL/SQL supports both static and ... Read More

In this problem, we are given three values: base, height and hypotenuse of a right triangle. Our task is to find the area and perimeter of the right triangle in PL/SQL.PL/SQL is a combination of SQL along with the procedural features of programming languagesLet's take an example to understand the problem, Input : height = 4, base = 3, hypotenuse = 5 Output : area = 6, perimeter = 12Explanation −1 + 22 + 333 + 4444 = 4800 Solution ApproachA simple approach to solve the problem is using the formula for the area and perimeter of the triangle.Area = ... Read More

In this post, we will understand the difference between ROLAP and MOLAP.ROLAPIt stands for Relational Online Analytical Processing.It is used for large volumes of data.The access time in ROLAP is slow.It stores data in the form of relation tables.The data in ROLAP is fetched from a data warehouse.It uses complex SQL queries.A static multidimensional view of the data is created in ROLAP.MOLAPIt stands for Multidimensional Online Analytical Processing.It is used for less/limited volumes of data.The access time is quick in MOLAP.Data is stored in a multidimensional array.Data is fetched from the MDDBs database.A sparse matrix is used in MOLAP.Dynamic multidimensional ... Read More