Final answer:
Yes, it is true that in Proc SQL you can join three or more tables, which allows for comprehensive data analysis and querying across multiple related data sources.
Step-by-step explanation:
It is true that we can join three or more tables in Proc SQL. This is a feature of SQL that allows for increased flexibility and power when managing and querying relational databases. In Proc SQL, which is part of the SAS software suite, you can join multiple tables using various types of joins such as INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN, depending on the nature of the data and the desired output. By joining tables, you can retrieve data that spans across multiple tables based on a related column, usually a foreign key. This capability is essential for complex data analysis and reporting tasks that require data consolidation from different related data sources.