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NEWID (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

Creates a unique value of type uniqueidentifier.

Transact-SQL syntax conventions

Syntax

NEWID ( )  

Note

Not supported in Azure Synapse serverless pools.

Return Types

uniqueidentifier

Remarks

NEWID() is compliant with RFC4122.

Examples

A. Using the NEWID function with a variable

The following example uses NEWID() to assign a value to a variable declared as the uniqueidentifier data type. The value of the uniqueidentifier data type variable is printed before the value is tested.

-- Creating a local variable with DECLARE/SET syntax.  
DECLARE @myid uniqueidentifier  
SET @myid = NEWID()  
PRINT 'Value of @myid is: '+ CONVERT(varchar(255), @myid)  

Here's the result set.

Value of @myid is: 6F9619FF-8B86-D011-B42D-00C04FC964FF  

Note

The value returned by NEWID is different for each computer. This number is shown only for illustration.

B. Using NEWID in a CREATE TABLE statement

Applies to: SQL Server

The following example creates the cust table with a uniqueidentifier data type, and uses NEWID to fill the table with a default value. In assigning the default value of NEWID(), each new and existing row has a unique value for the CustomerID column.

-- Creating a table using NEWID for uniqueidentifier data type.  
CREATE TABLE cust  
(  
 CustomerID uniqueidentifier NOT NULL  
   DEFAULT newid(),  
 Company VARCHAR(30) NOT NULL,  
 ContactName VARCHAR(60) NOT NULL,   
 Address VARCHAR(30) NOT NULL,   
 City VARCHAR(30) NOT NULL,  
 StateProvince VARCHAR(10) NULL,  
 PostalCode VARCHAR(10) NOT NULL,   
 CountryRegion VARCHAR(20) NOT NULL,   
 Telephone VARCHAR(15) NOT NULL,  
 Fax VARCHAR(15) NULL  
);  
GO  
-- Inserting 5 rows into cust table.  
INSERT cust  
(Company, ContactName, Address, City, StateProvince,   
 PostalCode, CountryRegion, Telephone, Fax)  
VALUES  
 ('Wartian Herkku', 'Pirkko Koskitalo', 'Torikatu 38', 'Oulu', NULL,  
 '90110', 'Finland', '981-443655', '981-443655')  
,('Wellington Importadora', 'Paula Parente', 'Rua do Mercado, 12', 'Resende', 'SP',  
 '08737-363', 'Brasil', '(14) 555-8122', '')  
,('Cactus Comidas para Ilevar', 'Patricio Simpson', 'Cerrito 333', 'Buenos Aires', NULL,   
 '1010', 'Argentina', '(1) 135-5555', '(1) 135-4892')  
,('Ernst Handel', 'Roland Mendel', 'Kirchgasse 6', 'Graz', NULL,  
 '8010', 'Austria', '7675-3425', '7675-3426')  
,('Maison Dewey', 'Catherine Dewey', 'Rue Joseph-Bens 532', 'Bruxelles', NULL,  
 'B-1180', 'Belgium', '(02) 201 24 67', '(02) 201 24 68');  
GO

C. Using uniqueidentifier and variable assignment

The following example declares a local variable called @myid as a variable of uniqueidentifier data type. Then, the variable is assigned a value by using the SET statement.

DECLARE @myid uniqueidentifier ;  
SET @myid = 'A972C577-DFB0-064E-1189-0154C99310DAAC12';  
SELECT @myid;  
GO  

D. Query random data with the NEWID() function

The following example queries a random record from the Production.Product table using the NEWID() function. To query more records randomly, increase the TOP value.

SELECT TOP 1 ProductID, Name, ProductNumber
FROM Production.Product
ORDER BY NEWID()
GO

See Also

NEWSEQUENTIALID (Transact-SQL)
ALTER TABLE (Transact-SQL)
CAST and CONVERT (Transact-SQL)
CREATE TABLE (Transact-SQL)
Data Types (Transact-SQL)
System Functions (Transact-SQL)
uniqueidentifier (Transact-SQL)
Sequence Numbers