How to Join Tables in SQL for Multi-Source Data Analysis
When we work with real datasets in data analysis, information rarely comes from a single table. Cus...
SQL
Learn SQL the way data analysts actually use it—queries, joins, aggregations, optimization tips, and interview-focused concepts with real examples.
How to Use SELECT DISTINCT in SQL to Remove Duplicates
When we start working with real datasets in data analysis, one issue appears very quickly—duplicate...
How to Handle NULL Values in Data Analytics Queries
When we start working with real-world data in data analysis, one thing becomes obvious very quickly...
How to Group Data with GROUP BY for Summary Reports
When we work with raw data, everything often looks overwhelming. Thousands of rows, repeating value...
How to Use Aggregate Functions in SQL for Data Analysis
When we start working with data, individual rows rarely give us meaningful answers. Looking at one ...
How to Sort Results with ORDER BY in SQL for Data Analysis
Have you ever written a SQL query, looked at the results, and felt something was off—not because th...
How to Clean Messy Data Using SQL for Data Analysis
Have you ever run a SQL query, felt confident about your logic, and then looked at the results thin...
How to Select Specific Columns in SQL?
When you start learning SQL, one of the first habits you pick up is using SELECT *. It works, and i...
SQL for Data Analysis: Queries, Joins, and Real-World Examples
When you step into the world of data analysis, SQL quickly becomes one of your most powerful tools....
Query Optimization in SQL: Techniques and Best Practices
When I first started writing SQL queries, I honestly only cared about getting the correct output. I...