VECTOR_NORM (Transact-SQL)

Applies to: SQL Server 2025 (17.x) Preview Azure SQL Database Azure SQL Managed Instance SQL database in Microsoft Fabric Preview

Use VECTOR_NORM to take a vector as an input and return the norm of the vector (which is a measure of its length or magnitude) in a given norm type.

For example, if you want to calculate the Euclidean norm (which is the most common norm type), you can use:

SELECT VECTOR_NORM ( vector, 'norm2' )
FROM ...

Syntax

Transact-SQL syntax conventions

VECTOR_NORM ( vector , norm_type )

Arguments

vector

An expression that evaluates to vector data type.

norm_type

A string with the name of the norm type to use to calculate the norm of the given vector. The following norm types are supported:

• norm1 - The 1-norm, which is the sum of the absolute values of the vector components.
• norm2 - The 2-norm, also known as the Euclidean Norm, which is the square root of the sum of the squares of the vector components.
• norminf - The infinity norm, which is the maximum of the absolute values of the vector components.

Return value

The function returns a float value that represents the norm of the vector using the specified norm type.

An error is returned if norm_type isn't a valid norm type and if the vector isn't of the vector data type.

Examples

Example 1

The following example creates a vector with three dimensions from a string with a JSON array.

DECLARE @v AS VECTOR(3) = '[1, 2, 3]';

SELECT VECTOR_NORM(@v, 'norm2') AS norm2,
       VECTOR_NORM(@v, 'norm1') AS norm1,
       VECTOR_NORM(@v, 'norminf') AS norminf;

The expected return values would be:

Example 2

The following example calculates the norm of each vector in a table.

CREATE TABLE dbo.vectors
(
    ID INT PRIMARY KEY,
    v VECTOR(3) NOT NULL
);

INSERT INTO dbo.vectors (ID, v)
VALUES
    (1, '[0.1, -2, 42]'),
    (2, '[2, 0.1, -42]');

SELECT ID, VECTOR_NORM(v, 'norm2') AS norm
FROM dbo.vectors;

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• Vector data type
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