When we all think of creating powerful dashboards in Tableau or Power BI, we jump straight into charts, filters, and KPIs. But the truth is, great visualization doesn’t start with design — it starts with data . Behind every fast, accurate, and insightful dashboard lies a strong foundation: data structure, data modeling, and understanding how OLTP and OLAP systems work . These concepts determine how smoothly your visualizations run, how quickly they respond, and how correctly

Writing a complex SQL query often involves using the result of one query inside another. This leads to the eternal SQL dilemma: Should...

In PostgreSQL, both Common Table Expressions (CTEs) and views offer powerful ways to simplify and organize complex queries. While they...