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PathName (Transact-SQL)

Returns the path of a FILESTREAM binary large object (BLOB). The OpenSqlFilestream API uses this path to return a handle that an application can use to work with the BLOB data by using Win32 APIs. PathName is read-only.

Topic link iconTransact-SQL Syntax Conventions

Syntax

column_name.PathName (@option)

Arguments

  • column_name
    Is the column name of a varbinary(max) FILESTREAM column. column_name must be a column name. It cannot be an expression nor the result of a CAST or CONVERT statement.

    Requesting the PathName for a column of any other data type or for a varbinary(max) columnthat does not have the FILESTREAM storage attribute will cause a query compile-time error.

  • @option
    An integer expression that defines how the server component of the path should be formatted. @option can be one of the following values. The default is 0.

    Value

    Description

    0

    Returns the server name converted to BIOS format, for example: \\SERVERNAME\MSSQLSERVER\v1\Archive\dbo\Records\Chart\A73F19F7-38EA-4AB0-BB89-E6C545DBD3F9

    1

    Returns the server name without conversion, for example: \\ServerName\MSSQLSERVER\v1\Archive\dbo\Records\Chart\A73F1

    2

    Returns the complete server path, for example: \\ServerName.MyDomain.com\MSSQLSERVER\v1\Archive\dbo\Records\Chart\A73F19F7-38EA-4AB0-BB89-E6C545DBD3F9

Return Type

nvarchar(max)

Return Value

The returned value is the fully qualified logical or NETBIOS path of the BLOB. PathName does not return an IP address. NULL is returned when the FILESTREAM BLOB has not been created.

Remarks

The ROWGUID column must be visible in any query that calls PathName.

A FILESTREAM BLOB can only be created by using Transact-SQL.

Examples

A. Reading the path for a FILESTREAM BLOB

The following example assigns the PathName to an nvarchar(max) variable.

DECLARE @PathName nvarchar(max)
SET @PathName = (
    SELECT TOP 1 photo.PathName()
    FROM dbo.Customer
    WHERE LastName = 'CustomerName'
    );

B. Displaying the paths for FILESTREAM BLOBs in a table

The following example creates and displays the paths for three FILESTREAM BLOBs.

-- Create a FILESTREAM-enabled database.
-- The c:\data directory must exist.
CREATE DATABASE PathNameDB
ON
PRIMARY ( NAME = ArchX1,
    FILENAME = 'c:\data\archdatP1.mdf'),
FILEGROUP FileStreamGroup1 CONTAINS FILESTREAM( NAME = ArchX3,
    FILENAME = 'c:\data\filestreamP1')
LOG ON  ( NAME = ArchlogX1,
    FILENAME = 'c:\data\archlogP1.ldf');
GO

USE PathNameDB;
GO

-- Create a table, add some records, and
-- create the associated FILESTREAM
-- BLOB files.

CREATE TABLE TABLE1
    (
        ID int,
        RowGuidColumn UNIQUEIDENTIFIER
                      NOT NULL UNIQUE ROWGUIDCOL,
        FILESTREAMColumn varbinary(MAX) FILESTREAM
    );
GO

INSERT INTO TABLE1 VALUES(1, NEWID(), 0x00);
INSERT INTO TABLE1 VALUES(2, NEWID(), 0x00);
INSERT INTO TABLE1 VALUES(3, NEWID(), 0x00);
GO

SELECT FILESTREAMColumn.PathName() AS 'PathName' FROM TABLE1;

--Results
--PathName
------------------------------------------------------------------------------------------------------------
--\\SERVER\MSSQLSERVER\v1\PathNameExampleDB\dbo\TABLE1\FILESTREAMColumn\DD67C792-916E-4A76-8C8A-4A85DC5DB908
--\\SERVER\MSSQLSERVER\v1\PathNameExampleDB\dbo\TABLE1\FILESTREAMColumn\2907122B-2560-4CB9-86DC-FBE7ABA1843B
--\\SERVER\MSSQLSERVER\v1\PathNameExampleDB\dbo\TABLE1\FILESTREAMColumn\922BE0E0-CAB9-4403-90BF-945BD258E4BC
--
--(3 row(s) affected)
GO

--Drop the database to clean up.
USE MASTER
GO
DROP DATABASE PathNameDB