Perform Complex JOINS in SQL
This course covers the execution of complex JOINs in SQL. It is aimed at people who already master the fundamentals of SQL JOINs and wish to deepen their knowledge with advanced technique...
The course concludes with a comparison of the behaviors of these JOINs between SQL Server, PostgreSQL and MySQL, highlighting the differences in syntax and compatibility between these platforms.
A SELF JOIN is a join of a table with itself. Unlike ordinary JOINs which combine columns from two different tables, the SELF JOIN exploits a self-referential relationship within the same table.
The SELF JOIN requires using table aliases to distinguish between two references to the same table in the query.
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What's inside
9 sections- 1 Table of Contents
- 2 Introduction
- 3 Demo: Queries on hierarchical data with SELF JOINS
- 4 Demo: Generation of combinations with CROSS JOINS
- 5 Demo: Merging incomplete data with FULL OUTER JOINS
- 6 Demo: Simplifying queries with the USING clause
- 7 Comparison of SQL JOINS between SQL platforms
- 8 Summary and best practices
- 9 Demo files
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