PostgreSQL - Joins in PostgreSQL
What is the primary benefit of using a self join on a table like
employees?What is the primary benefit of using a self join on a table like employees?
easy📝 Conceptual Q1 of 15
Step-by-Step Solution
Solution:
Step 1: Understand self join
A self join allows a table to be joined with itself, enabling comparison between rows.Step 2: Purpose in employees table
In the employees table, it helps relate employees to their managers or peers by comparing rows.Final Answer:
To compare rows within the same table based on related columns -> Option BQuick Check:
Self join compares rows in one table [OK]
Quick Trick: Self join compares rows within the same table [OK]
Common Mistakes:
- Confusing self join with joining two different tables
- Thinking self join duplicates data
- Assuming self join is used for deleting rows
Master "Joins in PostgreSQL" in PostgreSQL
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore PostgreSQL Quizzes