What Is the Difference Between Union and Union All?

UNION ALL Difference

UNION ALL keeps all of the records from each of the original data sets, UNION removes any duplicate records. UNION first performs a sorting operation and eliminates of the records that are duplicated across all columns before finally returning the combined data set.

Which is better union or union all?

UNION ALL is faster and more optimized than UNION. But we cannot use it in all scenarios. UNION ALL with SELECT DISTINCT is not equivalent to UNION.

What is the difference between union and union all Mcq?

What is the difference between UNION and UNION ALL? UNION command selects distinct and related information from two tables. On the other hand, UNION ALL selects all the values from both the tables.