Bird
0
0

What does the SQL EXCEPT operator do?

easy📝 Conceptual Q11 of 15
SQL - Set Operations
What does the SQL EXCEPT operator do?
AReturns rows from the first query that are not in the second query
BReturns rows common to both queries
CCombines all rows from both queries including duplicates
DDeletes rows from the first table that exist in the second
Step-by-Step Solution
Solution:

  1. Step 1: Understand the purpose of EXCEPT

    The EXCEPT operator compares two query results and returns only those rows that appear in the first query but not in the second.

  2. Step 2: Differentiate from other set operations

    Unlike INTERSECT which returns common rows, EXCEPT returns unique rows from the first set only.

  3. Final Answer:

    Returns rows from the first query that are not in the second query -> Option A

  4. Quick Check:

    EXCEPT = difference = unique first query rows [OK]
Quick Trick: EXCEPT returns what first query has but second does not [OK]
Common Mistakes:
MISTAKES
  • Confusing EXCEPT with INTERSECT
  • Thinking EXCEPT deletes rows
  • Assuming EXCEPT returns all combined rows

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions
More SQL Quizzes
Advanced Joins - Joining more than two tables - Quiz 8hard GROUP BY and HAVING - Why grouping is needed - Quiz 8hard INNER JOIN - How the join engine matches rows - Quiz 5medium INNER JOIN - INNER JOIN with table aliases - Quiz 11easy LEFT and RIGHT JOIN - LEFT JOIN preserving all left rows - Quiz 12easy Set Operations - Set operations with ORDER BY - Quiz 13medium Table Relationships - Referential integrity enforcement - Quiz 11easy Table Relationships - Why understanding relationships matters - Quiz 12easy Views - View as a saved query mental model - Quiz 14medium Views - Querying through views - Quiz 1easy