List of lectures for the course SQL, 28 quest level on JavaRush

Using CTEs to Make Complex Queries More Readable
SQL SELF
28 level,0 lecture
Learn how to use CTEs (Common Table Expressions) to make complex SQL queries more understandable, maintainable, and structured. Examples, comparisons with subqueries, tips for building reports step by step, and common mistakes — all to help you work more efficiently with databases.
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CTE vs Subqueries: When Should You Use Each?
SQL SELF
28 level,1 lecture
In this article, we’ll figure out when you should use CTEs (Common Table Expressions) and when subqueries are the way to go. You’ll learn how to pick the best tool for different jobs, what affects performance, and why code readability sometimes matters more than speed. Real-world examples and tips will help you make smart choices in your own projects.
Open
Query Optimization with CTE
SQL SELF
28 level,2 lecture
Learn how to use CTEs (Common Table Expressions) in PostgreSQL like a pro: we’ll break down materialization, index-based optimization, splitting up gnarly queries, and performance analysis. Real-world tips and common mistakes—everything you need to make your SQL queries fly!
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Examples of Complex Queries with Multiple CTEs
SQL SELF
28 level,3 lecture
In this article, you'll check out some examples of complex SQL queries that use multiple CTEs (Common Table Expressions). We'll look at practical problems from different areas to show how CTEs help structure and simplify multi-step analytical queries.
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Typical Mistakes When Working with CTEs and How to Avoid Them
SQL SELF
28 level,4 lecture
Check out the most common mistakes when using CTEs (Common Table Expressions) in PostgreSQL and other DBMSs: from issues with materialization and recursion to picking the wrong one between UNION and UNION ALL. Get some hands-on tips on optimization, commenting, and choosing between CTEs and temp tables.
Open