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Find non-common records in two tables (SQL EXCEPT or NOT IN)

SQLeasy0.3 min readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Pubmatic
Key Concepts Tested
sql
Expert AnswerPremium
62 wordsInterview-ready
EXCEPT: SELECT col FROM t1 EXCEPT SELECT col FROM t2 (A minus B). NOT IN: SELECT * FROM t1 WHERE col NOT IN (SELECT col FROM t2)—**NULL trap**: if t2 has NULL, NOT IN returns nothing. **Safe**: NOT EXISTS (SELECT 1 FROM t2 WHERE t2.col = t1.col). **EXCEPT** eliminates duplicates; NOT EXISTS doesn't....
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