Sophia Williams
Data Analyst
Articles by Sophia Williams
Database Transactions: ACID Properties Explained
Master ACID properties with examples, isolation anomalies, backup strategies, Spring @Transactional code, and troubleshooting. Read practical best pra...
Oracle Database Tutorial: Essential Concepts for Beginners
Learn Oracle Database basics—installation checks, SQL & PL/SQL examples, Data Pump, and admin best practices. Start building reliable databases today.
SQL Indexing Best Practices: Optimize Query Performance
Master SQL indexing for Postgres 12+ and SQL Server 2019+. Includes examples, maintenance tips, and troubleshooting—read and apply practical technique...
SQL Joins Explained: INNER, LEFT, RIGHT, and FULL JOIN
Learn INNER, LEFT, RIGHT, and FULL JOINs with diagrams, performance tips, and real-world troubleshooting. Apply these techniques to improve your SQL q...
Database Normalization: 1NF, 2NF, 3NF Explained Simply
Learn 1NF–3NF and BCNF with SQL examples, an SVG decomposition diagram, denormalization advice, security tips, and troubleshooting for MySQL 8.0 & Pos...
MySQL vs PostgreSQL: Database Comparison
Compare MySQL vs PostgreSQL performance, advanced SQL examples, and migration best practices. Learn troubleshooting and choose the right database—read...
MongoDB Basics: NoSQL Database for Modern Applications
Learn MongoDB v6.0: CRUD, advanced querying, scaling, performance tips, and security best practices with real examples. Start building scalable apps t...
PostgreSQL Tutorial for Beginners: Getting Started Guide
Learn PostgreSQL 15: install, create users, run queries, secure, and back up databases with practical examples. Start building today.
Mastering SQL Comments: A Comprehensive Guide
Learn practical SQL commenting techniques, real-world scenarios, security tips, and troubleshooting to improve query clarity and maintainability. Star...
Data Wrangling: Clean & Prep Your Data for Analysis
Practical data wrangling with Pandas 2.1, Python 3.9, and SQL. Learn cleaning, metrics, PII handling, and production patterns — try the mini-project.
Mastering Concatenation in SQL: A Comprehensive Guide
Master SQL concatenation across MySQL, PostgreSQL, SQL Server & Oracle. Learn compatibility, length limits, security and performance tips — read now.
Beginner's Guide to SQL Databases: A Step-by-Step Tutorial
Learn SQL databases with examples, transactions, and best practices for PostgreSQL and MySQL. Follow hands-on steps and build your first schema today.
Master SQL for Not Equal: Step-by-Step Tutorial
Learn SQL NOT EQUAL with NULL handling, COALESCE/IFNULL examples, indexing tips, and EXPLAIN troubleshooting. Try the examples and improve queries now...
Complete Guide to MySQL SUBSTR: Examples & Best Practices
Master MySQL SUBSTR syntax, edge cases, performance tips, and secure masking. Read examples and apply best practices in your ETL—start optimizing toda...
COALESCE in SQL: A Comprehensive Guide
Master COALESCE in SQL with practical examples, compatibility notes, and best practices. Learn how to handle NULLs and optimize queries—apply these ti...
Advanced Data Visualization Techniques
Master D3.js v7, Tableau 2023.3, Matplotlib 3.5 with runnable code, accessibility and performance tips. Follow live-demo guidance and try the examples...
Learn Database Optimization: A Guide for Improved Performance
Master advanced database optimization—indexing, query tuning, monitoring, and troubleshooting with examples and configs. Start optimizing your databas...