Welcome to SQL Query Examples at Codevisionz!

Are you ready to dive into the world of SQL and unlock the power of database management? Whether you are a beginner eager to learn the basics or an experienced developer seeking to expand your skill set, our SQL Query Examples are designed to guide you through every step of the process.

Here at Codevisionz, we understand the importance of practical learning. That’s why our examples cover a wide range of topics, from fundamental SQL commands to more complex operations involving joins, database extensions, and much more. Each tutorial is crafted with clarity and precision, ensuring you can apply what you learn directly to real-world scenarios.

Our examples are structured to help you:

  • Master the Basics: Learn the essential SQL syntax to query, update, and manage data efficiently.
  • Explore Advanced Techniques: Dive into complex queries with joins and subqueries to manipulate data across multiple tables.
  • Discover Database Extensions: Expand your expertise with platform-specific extensions that enhance SQL’s capabilities.
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SQL Basics

Comments in SQL
Creating Database Tables in SQL
Designing a Relational Schema for E-commerce: Customers, Products, and Orders
GROUB BY Example: Monthly Sales Summary by Department
GROUP BY Statement in SQL
In-Depth Guide to SQL Data Types
LIKE and ILIKE Statement in SQL
LIMIT Statement in SQL
Primary Keys and Foreign Keys in SQL
Sorting Products by Price, Stock, and Name
SQL Keywords: DML, DCL, DDL, TCL
SQL Statement Fundamentals

SQL JOINS

Inner Join Example: Analyzing E-commerce Orders
Introduction to Joins in SQL
Left Join Example: Full Product Catalog Analysis
SQL Full Outer Joins
SQL Inner Joins
SQL Left Joins (or LEFT OUTER JOIN)
SQL Right Joins (or RIGHT OUTER JOIN)

Views

Advantages of Using SQL Views
Best Practices in Using SQL Views
Creating and Managing SQL Views
Limitations and Considerations
Practical Applications and Examples
Types of SQL Views
What Are SQL Views?

Database Extensions

Best Practices and Considerations
Comparison of data types in PostgreSQL, MySQL and SQL Server
Introduction to Database-Specific Extensions
MySQL Extensions
PostgreSQL Extensions
SQL Server Extensions

Window Function

Analytics Functions
Example 1: Cumulative Sales
Example 2: Moving Average
Example 3: Employee Ranking
Example 4: Year-Over-Year Sales Change
Example 5: Top N Sales by Region
Introduction to SQL Window Function
OVER() and OVER(PARTITION BY)
PARTITION BY / ORDER BY
Ranking Functions
Window Frame
Window Functions – Evaluation Order