-------------Diff b/w Union and Unionall?

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-------------Diff b/w Union and Unionall?..

Answer / the_xxx

The main difference between UNION ALL and UNION is UNION
only selects distinct values, UNION ALL selects all values
(including duplicates).

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-------------Diff b/w Union and Unionall?..

Answer / abd hfz

UNION gives result set of only distinct values from both
tables where as UNION ALL selects all values including
duplicates.

Is This Answer Correct ?

1 Yes

1 No

-------------Diff b/w Union and Unionall?..

Answer / sridevi

UNION will give only distinct values where as UNION ALL gives all the values including duplicates.Performance wise UNION ALL is faster than UNION because UNION needs to exclude duplicates.

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