What is UNION,UNION ALL?
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Answer / sanjudharan
UNION : eliminates duplicates
UNION ALL: retains duplicates
Both these are used to combine the results of different
SELECT statements.
Suppose I have five SQL SELECT statements connected by
UNION/UNION ALL, how many times should I specify UNION to
eliminate the duplicate rows? -
Once.
| Is This Answer Correct ? | 22 Yes | 9 No |
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