UNION ALL

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UNION vs. UNION ALL in SQL Server

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Sometimes there is a need to combine data from multiple tables or views into one comprehensive dataset. This may be for like tables within the same database or maybe there is a need to combine like data across databases or even across servers. I have read about the UNION and UNION ALL commands, but how do these work and how do they differ?

2019-12-05

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Question of the Day

The Decoded Value

In SQL Server 2025, what is returned from this code: 

DECLARE @message VARCHAR(50) = 'Hello SQL Server 2025!';
DECLARE @encoded VARCHAR(MAX);

SET @encoded = BASE64_ENCODE(CAST(@message AS VARBINARY(1000)));
SELECT BASE64_DECODE(@encoded)

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