SQL - Table Constraints
When a foreign key is set with
ON UPDATE CASCADE, what occurs if the referenced primary key in the parent table changes?When a foreign key is set with ON UPDATE CASCADE, what occurs if the referenced primary key in the parent table changes?
easy📝 Conceptual Q1 of 15
Step-by-Step Solution
Solution:
Step 1: Understand ON UPDATE CASCADE
This option ensures that changes to the parent key propagate to the child foreign keys.Step 2: Effect on child table
When the parent key is updated, all referencing foreign keys in the child table are updated automatically to maintain referential integrity.Final Answer:
The foreign key values in the child table are automatically updated to match the new parent key values. -> Option DQuick Check:
ON UPDATE CASCADE updates child keys automatically [OK]
Quick Trick: ON UPDATE CASCADE updates child keys automatically [OK]
Common Mistakes:
MISTAKES- Thinking ON UPDATE CASCADE blocks parent key updates
- Assuming child keys become NULL
- Believing no change occurs in child keys
Master "Table Constraints" in SQL
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore SQL Quizzes