SQL Functions and Expressions
SQL Functions and Expressions: Comprehensive Guide,Master SQL functions and expressions for cleaner, smarter database queries.
Master Built-In SQL Functions, Expressions, and Data Manipulation Techniques Across All Major Databases
Ready to move beyond basic queries and unlock the full expressive power of SQL? This book shows you how to transform raw tables into insights using the functions, expressions, and patterns relied on by top data teams.
Overview
SQL Functions and Expressions is a practical IT book and programming guide for professionals who want to Master Built-In SQL Functions, Expressions, and Data Manipulation Techniques Across All Major Databases. Covering SQLite, PostgreSQL, MySQL, and SQL Server, this technical book dives deep into SQL built-in functions, string manipulation functions, numeric and mathematical functions, date and time functions, aggregate functions, window functions, analytical functions, statistical functions, ranking functions, and conditional expressions—showing how to compose complex SQL expressions for advanced filtering, data transformation techniques, cross-database compatibility, and query optimization. By combining clear explanations with proven patterns, it equips you to write portable, performant SQL that produces reliable results in production systems.
Who This Book Is For
- Data analysts and BI developers who want to turn business questions into repeatable, trustworthy insights. Learn to use window and aggregate functions to create metrics, cohorts, and dashboards that stakeholders can act on.
- Software engineers and data engineers who maintain services across multiple databases. Build cross-platform SQL with compatibility strategies, minimize vendor lock-in, and ship features faster with robust analytical queries.
- DBAs, aspiring SQL specialists, and career switchers aiming to level up. Master practical techniques that impress in interviews, accelerate on-the-job performance, and open doors to high-impact projects.
Key Lessons and Takeaways
- Design portable queries that work across SQLite, PostgreSQL, MySQL, and SQL Server. You’ll learn equivalences for common functions, safe defaults for null handling, and patterns to avoid engine-specific pitfalls while preserving intent.
- Apply analytical and window functions to real business problems. Compute rankings, percentiles, moving averages, running totals, and time-based comparisons; build segmentations with conditional expressions; and translate complex business logic into clear, testable SQL.
- Optimize for accuracy and speed. Use data transformation techniques for clean inputs, advanced filtering to reduce scan costs, and query optimization tips—like minimizing non-sargable predicates and leveraging function determinism—to improve performance without sacrificing readability.
Why You’ll Love This Book
It replaces guesswork with clarity. Each topic starts with the “what and why,” then walks through small, focused examples that scale to production-grade solutions, so you can map concepts directly to your daily work.
You get practical cross-database guidance at every step. Side-by-side compatibility notes, performance considerations, and best practices help you write queries that are both elegant and efficient—no matter which engine your team deploys.
How to Get the Most Out of It
- Follow a progression that mirrors real projects. Start with core categories—string manipulation functions, numeric and mathematical functions, and date and time functions—then move to aggregate functions and analytical patterns with window functions, and finish with advanced topics like complex SQL expressions and statistical functions.
- Translate examples into your own domain. Rebuild a report you maintain using ranking functions or conditional expressions; refactor a slow query using query optimization tips; and validate logic against edge cases, such as nulls, time zones, and outliers.
- Practice with mini-projects that reinforce learning. Create a cohort analysis using advanced filtering and window frames; cleanse messy inputs with string and date utilities; and produce a KPI dashboard that combines aggregates, analytical functions, and cross-database compatibility techniques.
Get Your Copy
Level up your queries, ship insights faster, and become the go-to problem solver for your team. If you work with data, this guide will pay dividends on day one.
