What is UNION,UNION ALL?

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What is UNION,UNION ALL?..

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.

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What is UNION,UNION ALL?..

Answer / sandeep

Correct answer..

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4 Yes

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