Consider two large tables orders(order_id, product_id) and inventory(product_id, stock), both sorted on product_id. Which join algorithm will PostgreSQL most likely use to join them on product_id?

medium📝 query result Q5 of 15

PostgreSQL - Performance Tuning

Consider two large tables orders(order_id, product_id) and inventory(product_id, stock), both sorted on product_id. Which join algorithm will PostgreSQL most likely use to join them on product_id?

ANested Loop Join

BMerge Join

CHash Join

DCross Join

Step-by-Step Solution

Solution:

Step 1: Analyze table properties
Both tables are large and sorted on the join key product_id.
Step 2: Consider join algorithms
Merge Join is efficient when inputs are sorted on join keys.
Step 3: Exclude other options
Nested Loop is inefficient for large tables; Hash Join does not require sorted inputs; Cross Join is unrelated.
Final Answer:
Merge Join -> Option B
Quick Check:
Sorted large tables favor Merge Join [OK]

Quick Trick: Sorted large tables joined on key use Merge Join [OK]

Common Mistakes:

Choosing Hash Join despite sorted inputs
Selecting Nested Loop for large tables
Confusing Cross Join with other join types

Master "Performance Tuning" in PostgreSQL

9 interactive learning modes - each teaches the same concept differently

Learn Why Deep Visual Try Challenge Project Recall Time

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions

Consider two large tables orders(order_id, product_id) and inventory(product_id, stock), both sorted on product_id. Which join algorithm will PostgreSQL most likely use to join them on product_id?

Step 1: Analyze table properties

Step 2: Consider join algorithms

Step 3: Exclude other options

Final Answer:

Quick Check:

Want More Practice?