Feb 28, 2023 · Find Duplicate Rows in SQL. Example 15. Count Duplicate Rows. Example 16. Find Common Records Between Tables. Example 17. Grouping Data with ROLLUP. Example 18. Conditional Summation. Example 19. Group Rows by a Range. Example 20. Compute a …

Complex queries in SQL don't need to be hard to write. Learn what they are, how to create them, and some examples in this article. When you start working with SQL, you'll learn about the SELECT query to get data from tables. You'll then learn a range of techniques such as using the keyword, joining to tables, and ordering your results.

Mar 16, 2025 · Learn how to tackle complex SQL queries with techniques like CTEs, proper indexing, and query modularization. Discover best practices for improving performance, readability, and maintainability across different database platforms.

Key techniques in complex SQL queries include subqueries, joins, unions, intersections, aggregate functions, window functions, common table expressions (CTEs), pivoting, recursive queries, string manipulation, date and time functions, and case statements.

Mar 21, 2023 · In this tutorial, we will discuss some of the most popular advanced SQL techniques and provide real-world applications for each. You can use window functions to perform calculations on a "window" of data that is defined by a particular subset of rows in a table.

Apr 17, 2024 · Here are the 15 advanced SQL concepts that will help to transform your queries and enhance your database expertise: Subqueries, known as nested queries, are a powerful feature of advanced SQL that allows you to embed a …

Therefore, in this article, I’ll try to cover the “magic” behind writing complex SELECT statements. As always, I’ll start with the data model we’ll be using. Before you start to write (complex) queries you should understand what is where – which tables stored what data. Also, you should understand the nature of relations between these tables.

Mar 25, 2025 · Subqueries allow users to break complex queries into smaller, more manageable parts. This makes it easier to retrieve and manipulate data in a structured way. ... The SELECT statement in SQL allows us to retrieve data from a database. We can use the SQL subquery with the SELECT statement to perform operations in SQL. Consider a table employees ...

Jan 29, 2025 · In today's data-driven world, mastering SQL goes far beyond basic table queries. While simple SELECT statements serve everyday needs, complex SQL queries become essential when dealing with sophisticated data structures and advanced business requirements.

Jan 29, 2025 · JSON and semi-structured data handling provides the flexibility needed for diverse data sources, while Common Table Expressions offer clarity and maintainability in complex queries. Window functions deliver powerful analytical capabilities essential for meaningful business insights.