PostgreSQL This document is written for absolute beginners. It explains, in a step-by-step and theory-oriented manner, how CSV files are loaded into PostgreSQL and prepared using basic SQL queries before being used. Each section is explained in simple language while maintaining professional and industry-standard terminology.… Read More
Mastering SQL SELECT Clauses: A Practical Guide for Beginners When working with relational databases, the SELECT statement is the most frequently used SQL command. It allows you to retrieve data from tables and analyze it according to your needs. But in real-world scenarios, simply selecting… Read More
SQL database (Oracle) In the field of Information Technology (IT), databases play a very important role in storing, managing, and retrieving data efficiently. One of the most widely used database systems in the world is the Oracle Database. Oracle is a powerful Relational Database Management… Read More
Data Manipulation Language (DML) in SQL Introduction In modern information systems, data plays a crucial role in decision-making, automation, and business operations. Almost every application—banking systems, hospital management software, e-commerce platforms, social media applications, and educational portals—relies on databases to store and manage data efficiently.… Read More
PostgreSQL Commands and Data Types – A Complete Overview Introduction PostgreSQL is a powerful, open-source relational database management system widely used in modern applications. It is known for its reliability, performance, and rich support for advanced data types. Understanding SQL commands and PostgreSQL data types… Read More
Introduction to SQL Commands (DDL, DML,DQL, DCL, TCL) Beginner-Friendly Professional Documentation 1. SQL Basics & Command Categories What is SQL? SQL (Structured Query Language) is a standard language used to manage and interact with databases. Databases store data in the form of tables (rows and… Read More
Data Retrieval language(DRL) Data Retrieval Language (DRL) is a part of SQL used to retrieve (fetch) data from a database without modifying it. Main Command: SELECT – used to get data from one or more tables. Examples: SELECT * FROM students; → Retrieves all records… Read More
Data Definition Language (DDL) Introduction Structured Query Language (SQL) is the standard language used for interacting with relational databases. SQL is divided into different categories based on the type of operations performed on the database. Among these categories, Data Definition Language (DDL) plays a foundational… Read More
PostgreSQL: An In-Depth Overview of a Powerful Open-Source Database In today’s data-driven world, databases play a crucial role in storing, managing, and processing information efficiently. Almost every modern application—whether a web application, mobile app, enterprise system, or research platform—relies on a database at its core.… Read More
PostgreSQL Installation & Setup on macOS Introduction to PostgreSQL What is PostgreSQL? PostgreSQL is a powerful, open-source relational database management system (RDBMS). It is widely used by startups, enterprises, and developers because it is reliable, scalable, and similarly follows SQL standards. PostgreSQL supports: ● Structured… Read More
Introduction to SQL What is SQL? SQL (Structured Query Language) is a database computer language used to communicate with and retrieve data from relational databases. It allows users to store, manipulate, update, and retrieve data efficiently. SQL is widely used with popular database systems such… Read More
Linux / UNIX PATH, ls Command and File Access Permissions (Security) Introduction Linux and UNIX are powerful open-source operating systems widely used in servers, cloud platforms, development environments, and academic institutions. To work efficiently in Linux/UNIX, it is very important to understand PATH concepts, the… Read More
Linux / UNIX File and Directory Management Commands Introduction Linux and UNIX are powerful, open-source operating systems widely used in servers, cloud platforms, development environments, and academic institutions. File and directory management is a fundamental skill for working efficiently in UNIX/Linux systems. These operating systems… Read More
SQL SERVER INSTALLATION INTERNALS Installing Microsoft SQL Server is often treated as a routine DBA task : launch the installer, click Next a few times and wait for the green checkmark. But under the hood, SQL Server setup performs a carefully controlled sequence of validations,… Read More
Basics of UNIX Operating System UNIX is an operating system, similar to Windows. An operating system is a collection of multiple software programs that manages all the resources of a computer such as the CPU, memory, and storage. UNIX can be understood in the following… Read More
Understanding SQL Server Architecture Microsoft SQL Server is a relational database management system (RDBMS) designed to store, manage and retrieve data efficiently. To achieve high performance, reliability and scalability SQL Server is structured into several inter-related components that work together to process user queries, manage… Read More
MySQL Installation 2- Types of installation packages 1- MySQL Installation using generic binaries In this we can select the version (older version of MySQL) 2- MySQL Installation using YUM on RHEL Which is available with Repositories, supported latest version (APT=GET) Through Putty we connect by… Read More
Automating OSWatcher Log Capture with oswlogs_capture.sh Monitoring system performance is essential for ensuring stability, especially in production environments. Oracle’s OSWatcher (OSWbb) is a powerful tool that continuously captures vital operating system metrics. However, extracting logs for specific time periods can be cumbersome without a bit… Read More
COMPRESSION IN CASSANDRA Operators can set up compression on a per-table basis with Cassandra. By compressing the SSTable in user-configurable compression chunk_length_in_kb, compression minimizes the amount of data on disk. The CPU cost of compressing data is only required when the SSTable is written since… Read More
INSTALLING CASSANDRA USING DEBIAN PACKAGES Debain Package: It is a collection of files which are used to implement a set of features or commands. You can only use the Debain packages on Ubuntu and other Debain-based distributions. STEP-1: Java setup Check the version of Java… Read More
