Set Operators in SQL Server.

Hi Friends,in this post i would like to explain Set Operators in SQL Server.

*Set Operators are used to combined the data from multiple tables.

Set Operators:
1)UNION
2)UNION ALL
3)INTERSECT
4)EXCEPT

Syntax:
Select query1

Select query2

Select query3

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......
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1)UNION
*UNION can select only distinct/unique rows & rows can be arranged in ascending order.

2)UNION ALL
*UNION ALL is used to combine all rows from the given select queries.

3)INTERSECT
* UNION ALL is used to select only common rows from the given set of select queries.

4)EXCEPT
* EXCEPT is equalent to Minus operator in Oracle.To select all rows from the first query,except second query output.

Limitations:
* All queries should have equal number of columns.
* Corresponding column data types should be same.

Thank you...