Introduction
Relational databases usually contain multiple tables that are linked by common key fields. This normalized design minimizes duplication of data, but means that you'll often need to write queries to retrieve related data from two or more tables.
In this module, you'll learn how to:
- Understand join concepts and syntax
- Write queries that use inner joins
- Write queries that use outer joins
- Write queries that use cross joins
- Write queries that use self-joins