Nov 18, 2025 · Concatenates the results of two queries into a single result set. You control whether the result set includes duplicate rows: UNION ALL - Includes duplicates. UNION - Excludes duplicates. A …

The UNION operator is used to combine the result-set of two or more SELECT statements. The UNION operator automatically removes duplicate rows from the result set.

This tutorial shows you how to use the SQL UNION operator to combine the result sets of two queries into a single result set.

Jul 15, 2025 · In MS SQL Server, the UNION and UNION ALL operators are used to combine the result sets of two or more SELECT statements into a single result set. This allows you to retrieve data from …

Sep 8, 2008 · Both UNION and UNION ALL concatenate the result of two different SQLs. They differ in the way they handle duplicates. UNION performs a DISTINCT on the result set, eliminating any …

There are (at least) three ways to combine results of queries in SQL: JOIN, UNION, and INTERSECT. They serve different purposes: Use UNION when you want to add more rows to your results. Use …

Sep 20, 2016 · UNION and UNION ALL come into play here. Both are handy tools for stacking the results of two or more SELECT statements on top of each other, but they handle repeats differently.

Step-by-step comparison of UNION vs UNION ALL. Learn how to combine result sets, remove duplicates, preserve duplicates, and optimize queries with examples.

Jul 21, 2025 · UNION and UNION ALL are essential SQL tools for combining query results. Whether you're aggregating records from partitions or unifying multi-system data, knowing how to use these …

In summary, the UNION operator in SQL Server is a useful tool for combining the results of multiple SELECT statements into a single result set. It allows you to retrieve data from different tables or …