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Discuss Primary, Foreign, and Composite Keys.

General/Othermedium0.3 min readPremium
Frequency
Low
Asked at 1 company
Category
243
questions in General/Other
Difficulty Split
151E|43M|49H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Datametica
Key Concepts Tested
join
Expert AnswerPremium
51 wordsInterview-ready
**PK**: Uniquely identifies row; NOT NULL + unique. Surrogate (auto-increment) vs. natural. Surrogate preferred for stability. **FK**: References PK in another table; referential integrity. Index FKs for join performance. **Composite**: Multiple columns for uniqueness—e.g., (order_id, line_item_id)....
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