SQL Server 2012 introduces the CONCAT function

SQL Server 2012 has added some new system functions, a brief introduction to the Concat

The CONCAT function can connect up to 255 character variables, and when you call this function you need to receive at least two arguments, the parameter type is not necessarily a string type, or it can be implicitly converted to a string type such as int, float, and so on. As long as the rules that match SQL 2012 can be implicitly converted to strings, when we want to connect two value types of data, we do not need to convert them to nvarchar and then connect by "+".

If the passed parameter is NULL, it is implicitly converted to an empty string, and if all input parameters are null, an empty string of type VARCHAR (1) is returned.

Grammar rules

SELECT CONCAT (string_value1, String_value2, String_value3 [, String_valuen])--

Instance:

DECLARE @a VARCHAR = ' Jim is now '

DECLARE @b int=10

DECLARE @c VARCHAR = ' years old '

Select CONCAT (@a, @b, @c)

Go

Returns:

Jim is now years old

The top does not use an explicit conversion to convert int to varchar, and if you don't use concat, I might need to do this.

DECLARE @a VARCHAR = ' Jim is now '

DECLARE @b int=10

DECLARE @c VARCHAR = ' years old '

SELECT @a+convert (VARCHAR, (@b)) +@c

Go;

Returns:

Jim is now years old

Below are the types of input and output parameters:

Below are the types of input and output parameters:

Input value/type	Output value/type
Sql-clr (TY PES & UDT)	NVARCHAR (MAX)
NVARCHAR (max)	NVARCHAR (max)
NVARCHAR (<=4000)	NVARCHAR (<=4000)
VARBINARY (MAX)	NVARCHAR (MA X)
All other INPUT TYPES	VARCHAR (<=8000) *unless one of the ParamEters is a NVARCHAR   of any length, the output value would being in NVARCHAR (MAX)

SQL Server 2012 There are many other new functions to join

Conversion functions
PARSE	PARSE
Try_convert	Try_convert
Try_parse	Try_parse
Date and Time functions
Datefromparts	Datefromparts
Datetime2fromparts	Datetime2fromparts
Datetimefromparts	Datetimefromparts
Datetimeoffsetfromparts	Datetimeoffsetfromparts
EOMONTH	EOMONTH
Smalldatetimefromparts	Smalldatetimefromparts
Timefromparts	Timefromparts
Logical functions
CHOOSE	CHOOSE
Iif	Iif
String functions
Concat	Concat
FORMAT	FORMAT