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GetFileNamespacePath (Transact-SQL)

Applies to: SQL Server

Returns the UNC path for a file or directory in a FileTable.

Syntax

  
<column-name>.GetFileNamespacePath(is_full_path, @option)  

Arguments

column-name
The column name of the VARBINARY(MAX) file_stream column in a FileTable.

The column-name value must be a valid column name. It cannot be an expression, or a value converted or cast from a column of another data type.

is_full_path
An integer expression that specifies whether to return a relative or an absolute path. is_full_path can have one of the following values:

Value Description
0 Returns the relative path within the database-level directory.

This is the default value
1 Returns the full UNC path, starting with the \\computer_name.

@option
An integer expression that defines how the server component of the path should be formatted. @option can have one of the following values:

Value Description
0 Returns the server name converted to NetBIOS format, for example:

\\SERVERNAME\MSSQLSERVER\MyDocumentDatabase

This is the default value.
1 Returns the server name without conversion, for example:

\\ServerName\MSSQLSERVER\MyDocumentDatabase
2 Returns the complete server path, for example:

\\ServerName.MyDomain.com\MSSQLSERVER\MyDocumentDatabase

Return Type

nvarchar(max)

If the SQL Server instance is clustered in a failover cluster, then the machine name that is returned as part of this path is the virtual hostname for the clustered instance.

When the database belongs to an Always On availability group, then the FileTableRootPath function returns the virtual network name (VNN) instead of the computer name.

General Remarks

The path that the GetFileNamespacePath function returns is a logical directory or file path in the following format:

\\<machine>\<instance-level FILESTREAM share>\<database-level directory>\<FileTable directory>\...

This logical path does not directly correspond to a physical NTFS path. It is translated to the physical path by FILESTREAM's file system filter driver and the FILESTREAM agent. This separation between the logical path and physical path lets SQL Server reorganize data internally without affecting the validity of the path.

Best Practices

To keep code and applications independent of the current computer and database, avoid writing code that relies on absolute file paths. Instead, get the complete path for a file at run time by using the FileTableRootPath and GetFileNamespacePath functions together, as shown in the following example. By default, the GetFileNamespacePath function returns the relative path of the file under the root path for the database.

USE MyDocumentDatabase;  
@root varchar(100)  
SELECT @root = FileTableRootPath();  
  
@fullPath = varchar(1000);  
SELECT @fullPath = @root + file_stream.GetFileNamespacePath() FROM DocumentStore  
WHERE Name = N'document.docx';  

Remarks

Examples

The following examples show how to call the GetFileNamespacePath function to get the UNC path for a file or directory in a FileTable.

-- returns the relative path of the form "\MyFileTable\MyDocDirectory\document.docx"  
SELECT file_stream.GetFileNamespacePath() AS FilePath FROM DocumentStore  
WHERE Name = N'document.docx';  
  
-- returns "\\MyServer\MSSQLSERVER\MyDocumentDatabase\MyFileTable\MyDocDirectory\document.docx"  
SELECT file_stream.GetFileNamespacePath(1, Null) AS FilePath FROM DocumentStore  
WHERE Name = N'document.docx';  

See Also

Work with Directories and Paths in FileTables