REVERSE (Transact-SQL)

Artikel
09/03/2024

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Returns the reverse order of a string value.

Transact-SQL syntax conventions

Syntax

REVERSE ( string_expression )

Arguments

string_expression
string_expression is an expression of a string or binary data type. string_expression can be a constant, variable, or column of either character or binary data.

Return Types

varchar or nvarchar

Remarks

string_expression must be of a data type that is implicitly convertible to varchar. Otherwise, use CAST to explicitly convert string_expression.

Supplementary Characters (Surrogate Pairs)

When using SC collations, the REVERSE function will not reverse the order of two halves of a surrogate pair.

Examples

The following example returns all contact first names with the characters reversed. This example uses the AdventureWorks2022 database.

SELECT FirstName, REVERSE(FirstName) AS Reverse  
FROM Person.Person  
WHERE BusinessEntityID < 5  
ORDER BY FirstName;  
GO

Here's the result set.

FirstName      Reverse
-------------- --------------
Ken            neK
Rob            boR
Roberto        otreboR
Terri          irreT

(4 row(s) affected)

The following example reverses the characters in a variable.

DECLARE @myvar VARCHAR(10);  
SET @myvar = 'sdrawkcaB';  
SELECT REVERSE(@myvar) AS Reversed ;  
GO

The following example makes an implicit conversion from an int data type into varchar data type and then reverses the result.

SELECT REVERSE(1234) AS Reversed ;  
GO

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

The following example returns names of all databases, and the names with the characters reversed.

SELECT name, REVERSE(name) FROM sys.databases;  
GO

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