Course
UNION vs UNION ALL in SQL
Discover the output and performance differences between UNION and UNION ALL: UNION removes duplicates while UNION ALL includes them.
Jul 19, 2024 · 7 min read
What is the primary difference between SQL UNION and UNION ALL?
Is there a performance difference between UNION and UNION ALL?
Are there specific use cases where UNION ALL is preferred over UNION?
When should I use SQL UNION instead of UNION ALL?
How do different SQL dialects affect the use of UNION and UNION ALL?
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