Data Science Educational Resources
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SQL Articles, Tutorials & Interview Questions
Mastering Row Number Handling in SQL Queries
ROW_NUMBER() is one of the essential ranking window functions in SQL. Learn where you can use it and how it works with ORDER BY and PARTITION BY window clauses.
Nathan Rosidi -
Finding Maximum Values in SQL: Aggregation Techniques
MAX() in SQL is a straightforward aggregation method for finding maximum values. Learn here about its syntax and use cases through real interview examples.Nathan Rosidi -
CONCAT() in SQL: Tips and Techniques for Efficient Queries
CONCAT() in SQL is a data concatenation method. Learn about the tips, techniques, and practical examples of how to use it efficiently in SQL queries.Nathan Rosidi -
PySpark SQL Functions: Boost Big Data Processing with SQL
Leverage PySpark SQL Functions to efficiently process large datasets and accelerate your data analysis with scalable, SQL-powered solutions.Nathan Rosidi -
Counting Distinct Values in SQL: Tips and Examples
Using SQL COUNT(DISTINCT) is an easy way to count distinct values in SQL. However, it has its own quirks, which we’ll explain (with examples) in this article.Nathan Rosidi -
How Do You Perform SQL LIKE Queries for Pattern Matching?
The LIKE SQL query allows you to perform a pattern-matching search of your text data. Learn how to use it and add wildcards for increased flexibility.Nathan Rosidi -
Utilizing DENSE_RANK for Data Deduplication in SQL
Data deduplication in SQL can be done in several ways. Using DENSE_RANK() is one. Today, we’ll talk about using this function to improve your data’s quality.Nathan Rosidi -
SQL PARTITION BY: Advanced Analytical Insights
SQL PARTITION BY makes SQL window functions – already a powerful analytical tool – even more suitable for advanced analytical insights from your data.Nathan Rosidi -
What Are the Steps to Cast INT in SQL for Type Conversion?
Cast INT in SQL is a must-know for anyone even remotely interested in data handling and analysis. This article will cover all the important cast INT topics.Nathan Rosidi -
How to Use SQL Wildcards for Flexible Data Queries
This article is all about uncertainty and using it to add flexibility to SQL queries. How do you do that? Start using one of the five SQL wildcards regularly.Nathan Rosidi -
How Does SQL Date Formatting Work?
In this article, we explore the SQL date format. We’ll deal with how standard and custom date formatting work in four of the most popular SQL flavors.Nathan Rosidi -
Simplifying SQL Queries with Aliases: A How-To Guide
SQL aliases are a simple yet efficient way of simplifying your SQL queries. In this guide, we’ll show you all the benefits and provide examples of their use.Nathan Rosidi -