Hierarchical SQL Queries: Databases for Developers #16
Often data contains a parent-child relationship between rows in the same table. For example, company org charts and family trees.
You can use the power of SQL to traverse these hierarchical relationships. There are two ways to do this in Oracle Database:
Connect By
Recursive With
Watch this video to learn about data trees and find out how these work!
Further reading:
Hierarchical queries in the docs: https://docs.oracle.com/en/database/o...
Recursive subquery factoring in 11.2: https://oracle-base.com/articles/11g/...
Take the course! https://devgym.oracle.com/pls/apex/dg...
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The Magic of SQL with Chris Saxon
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