What are UNION and UNION ALL in DB2? How do you differentiate between

1.	What are UNION and UNION ALL in DB2? How do you differentiate between them?
Answer» The union command is used to merge 2 or more SELECT STATEMENTS and the select statements can be APPLIED on a single table as well as on multiple TABLES. The major difference between UNION and UNION ALL is that UNION removes the duplicate rows when it is applied on the tables whereas UNION ALL retains the duplicates.

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