Get FileTable stream_id after creating image with File I/O Api

Question

I tried inserting an image file into SQL Server FileTable directory with File I/O API. I need to get stream_id of inserted image and use it another table as a foreign key.

Can anyone help me, how can I get created image stream_id?

Answer 1

After creating the file, you'll need to query the file table using T-SQL with the newly created file path to get the stream_id. This is best done using the unique file table path_locator column.

Below are example stored procedure and usage examples that get the unique stream_id of the file using either the relative or full UNC path. The path_locator of file tables has a unique constraint index so these queries are very efficient.

CREATE DATABASE FileTableExample
    ON  PRIMARY 
    ( NAME = N'FileTableExample', FILENAME = N'D:\SqlFiles\FileTableExample.mdf' , SIZE = 8192KB , MAXSIZE = UNLIMITED, FILEGROWTH = 10MB ), 
     FILEGROUP FileStreamFG CONTAINS FILESTREAM  DEFAULT
    ( NAME = N'FileTableExample_FileStream', FILENAME = N'D:\SqlFiles\FileTableExample_FileStreamFG' , MAXSIZE = UNLIMITED) 
     LOG ON 
    ( NAME = N'FileTableExample_log', FILENAME = N'D:\SqlFiles\FileTableExample_log.ldf' , SIZE = 10MB , MAXSIZE = UNLIMITED, FILEGROWTH = 10MB );
GO

ALTER DATABASE FileTableExample SET FILESTREAM( NON_TRANSACTED_ACCESS = FULL, DIRECTORY_NAME = N'FileTableExample' ) 
GO

USE FileTableExample;
GO

CREATE TABLE [dbo].[Images] AS FILETABLE ON [PRIMARY] FILESTREAM_ON [FileStreamFG];
WITH
(
    FILETABLE_DIRECTORY = N'Images', FILETABLE_COLLATE_FILENAME = SQL_Latin1_General_CP1_CI_AS
);
GO

CREATE PROC dbo.GetStreamIDByRelativePath
    @RelativeFilePath nvarchar(MAX)
AS
SELECT stream_id
FROM dbo.Images
WHERE path_locator = GetPathLocator(FileTableRootPath() + @RelativeFilePath);
GO

EXEC dbo.GetStreamIDByRelativePath @RelativeFilePath = N'\Images\YourImageFile.png';
GO

CREATE PROC dbo.GetStreamIDByFullUNCPath
    @FullUNCPath nvarchar(MAX)
AS
SELECT stream_id
FROM dbo.Images
WHERE path_locator = GetPathLocator(@FullUNCPath);
GO

EXEC dbo.GetStreamIDByFullUNCPath @FullUNCPath = N'\\YourSqlServer\YourFileStreamShare\YourDatabaseFileSteamDirectory\Images\YourImageFile.png';
GO