How To Use UNION to Merge Outputs from Two Queries Together in SQL Server?

If you have two queries that returns the same row fields, you can merge their outputs together with the UNION operator. The following tutorial exercise shows you how to use the UNION operator:

SELECT * FROM fyi_links WHERE tag = 'DBA'
GO
id   url                notes  counts  created     tag
102  dba.fyicenter.com  NULL   972     2007-05-19  DBA
104  www.mysql.com             390     2006-01-01  DBA
105  www.oracle.com            960     2005-01-01  DBA

SELECT * FROM fyi_links WHERE tag = 'DEV'
GO
id   url                notes  counts  created     tag
101  dev.fyicenter.com  NULL   120     2006-04-30  DEV
106  www.php.net               439     2004-01-01  DEV

SELECT * FROM fyi_links WHERE tag = 'DBA'
UNION
SELECT * FROM fyi_links WHERE tag = 'DEV'
GO
id   url                notes  counts  created     tag
102  dba.fyicenter.com  NULL   972     2007-05-19  DBA
104  www.mysql.com             390     2006-01-01  DBA
105  www.oracle.com            960     2005-01-01  DBA
101  dev.fyicenter.com  NULL   120     2006-04-30  DEV
106  www.php.net               439     2004-01-01  DEV

⇒ Using ORDER BY with UNION Operators in SQL Server

⇐ Returning the Second 5 Rows from a Query in SQL Server

⇑ Using SELECT Statements with Joins and Subqueries in SQL Server

⇑⇑ SQL Server Database Tutorials