A new method of implementing string concatenation in SQL Server 2012

Before the--sqlserver 2012 version

/* Handling NOT NULL characters/*

DECLARE @t1 varchar (a) = ' a '

DECLARE @t2 varchar (+) = ' B '

DECLARE @t3 varchar (+) = ' C '

DECLARE @t4 varchar (+) = ' d '

DECLARE @N1 int = 2012

SELECT @t1 + @t2 + @t3 + @t4 +convert (varchar), @N1) as result

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/* Handle NULL characters/*

DECLARE @t1 varchar (a) = ' a '

DECLARE @t2 varchar (+) = ' B '

DECLARE @t3 varchar (TEN) = null

DECLARE @t4 varchar (+) = ' d '

DECLARE @N1 int = 2012

SELECT @t1 + @t2 +isnull (@t3, ') + @t4 +convert (varchar), @N1) as result

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If the IsNull is not used here, then the value we get will be null, quite different from what we expect.

---SQL Server 2012

SELECT CONCAT (' A ', ' B ', ' C ', ' d ', ', ') as result

Go

/* Handling NOT NULL characters/*

DECLARE @t1 varchar (a) = ' a '

DECLARE @t2 varchar (+) = ' B '

DECLARE @t3 varchar (+) = ' C '

DECLARE @t4 varchar (+) = ' d '

DECLARE @N1 int = 2012

SELECT CONCAT (@t1, @t2, @t3, @t4, @N1) as result

Go

/* Handle NULL characters/*

DECLARE @t1 varchar (a) = ' a '

DECLARE @t2 varchar (+) = ' B '

DECLARE @t3 varchar (TEN) = null

DECLARE @t4 varchar (+) = ' d '

DECLARE @N1 int = 2012

SELECT CONCAT (@t1, @t2, @t3, @t4, @N1) as result

Go

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