Recursive CTEs

Self Joins

Window Functions for Hierarchies

Graph Algorithms in SQL

Materialized Views

Query Optimization

Build complete org chart with levels, paths, and team sizes

Create e-commerce category tree with product counts

Explode bill-of-materials with quantity rollup and cost calculation

Find all subordinates of a manager (top-down traversal)

Find reporting chain from employee to CEO (bottom-up traversal)

Calculate subtree sizes for each node in hierarchy

Implement cycle detection for graphs with circular references

Build file system hierarchy with folder sizes

Create social network friend-of-friend query (2-3 degrees)

Optimize recursive query with indexes and materialized views

Explain how recursive CTEs work for hierarchical data

How do you prevent infinite recursion?

What's the difference between top-down and bottom-up traversal?

How do you calculate subtree sizes?

How do you optimize recursive queries for large hierarchies?

How do you handle circular references in graphs?

When should you use recursive CTEs vs closure tables?

Write a query to build an org chart with levels and paths

Write a query to find all subordinates of a manager

Write a query to explode a bill-of-materials with cost rollup

PostgreSQL Recursive Queries Documentation

Hierarchical Data in SQL: Recursive CTEs vs Closure Tables

Graph Algorithms in SQL

Optimizing Recursive Queries

Bill of Materials Design Patterns

Materialized Path vs Nested Sets for Hierarchies