With the release of SQL Server 2025 RC0, we have enabled the ability to use a local ONNX model on the server for embeddings. This allows you to use these models without having any network traffic leaving the local environment.Getting StartedThis example guides you through setting up SQL Server 2025 on Windows with an ONNX runtime to enable local AI-powered text embedding generation. ONNX Runtime is an open-source inference engine that allows you to run machine learning models locally, making it ideal for integrating AI capabilities into SQL Server environments.[alert type="important" heading="Important"]This feature requires that SQL Server Machine Learning Services is installed.[/alert]Step 1: Enable developer preview features on SQL Server 2025Run the following SQL command to enable SQL Server 2025 preview features in the database you would like use for this example:ALTER DATABASE SCOPED CONFIGURATIONSET PREVIEW_FEATURES = ON;Step 2: Enable the local AI runtime on SQL Server 2025Enable external AI runtimes by running the following SQL:EXEC sp_configure 'external AI runtimes enabled', 1;RECONFIGURE WITH OVERRIDE;Step 3: Set up the ONNX runtime libraryCreate a directory on the SQL Server to hold the ONNX runtime library files. In this example, C:\onnx_runtime is used.You can use the following PowerShell commands to create the directory:cd C:\mkdir onnx_runtimeNext, download the ONNX Runtime (version ≥ 1.19) that is appropriate for your operating system.After unzipping the download, copy the onnxruntime.dll (located in the lib directory) to the C:\onnx_runtime directory that was created.Step 4: Set up the tokenization libraryDownload and build the tokenizers-cpp library from GitHub. Once the dll is created, place the tokenizer in the C:\onnx_runtime directory.[alert type="important" heading="Important"]Ensure the created dll is named tokenizers_cpp.dll.[/alert]Easy ButtonTo make this process easy to get you started, our engineering team has created the file for you for the model that will be downloaded in the next step.You can download it here.Just be sure to rename it to tokenizers_cpp.dll.Step 5: Download the ONNX modelStart by creating the model directory in C:\onnx_runtime\.cd C:\onnx_runtimemkdir modelThis example uses the all-MiniLM-L6-v2-onnx model from Hugging Face, which can be downloaded here.Clone the repository into the C:\onnx_runtime\model directory with the following git command:If not installed, you can download git from the following download link or via winget (winget install Microsoft.Git)cd C:\onnx_runtime\modelgit clone https://huggingface.co/nsense/all-MiniLM-L6-v2-onnxStep 6: Set directory permissionsUse the following PowerShell script to provide the MSSQLLaunchpad user access to the ONNX runtime directory:$AIExtPath = "C:\onnx_runtime";$Acl = Get-Acl -Path $AIExtPath$AccessRule = New-Object System.Security.AccessControl.FileSystemAccessRule("MSSQLLaunchpad", "FullControl", "ContainerInherit,ObjectInherit", "None","Allow")$Acl.AddAccessRule($AccessRule)Set-Acl -Path $AIExtPath -AclObject $AclStep 7: Create the external modelRun the following SQL to register your ONNX model as an external model object:The 'PARAMETERS' value used here is a placeholder needed for SQL Server 2025 RC 0.CREATE EXTERNAL MODEL myLocalOnnxModelWITH (LOCATION = 'C:\onnx_runtime\model\all-MiniLM-L6-v2-onnx',API_FORMAT = 'ONNX Runtime',MODEL_TYPE = EMBEDDINGS,MODEL = 'allMiniLM',PARAMETERS = '{"valid":"JSON"}',LOCAL_RUNTIME_PATH = 'C:\onnx_runtime\');[alert type="important" heading="Important"]LOCATION should point to the directory containing model.onnx and tokenizer.json files.LOCAL_RUNTIME_PATH should point to directory containing onnxruntime.dll and tokenizer_cpp.dll files. [/alert]Step 8: Generate embeddingsUse the ai_generate_embeddings function to test the model by running the following SQL:SELECT ai_generate_embeddings (N'Test Text' USE MODEL myLocalOnnxModel);This command launches the AIRuntimeHost, load the required DLLs, and processes the input text.The result from the SQL statement is an array of embeddings:[0.320098,0.568766,0.154386,0.205526,-0.027379,-0.149689,-0.022946,-0.385856,-0.039183...]Enable XEvent telemetryRun the following SQL to enable telemetry for troubleshooting.CREATE EVENT SESSION newevtON SERVERADD EVENT ai_generate_embeddings_airuntime_trace(ACTION (sqlserver.sql_text, sqlserver.session_id))ADD TARGET package0.ring_bufferWITH (MAX_MEMORY = 4096 KB, EVENT_RETENTION_MODE = ALLOW_SINGLE_EVENT_LOSS, MAX_DISPATCH_LATENCY = 30 SECONDS, TRACK_CAUSALITY = ON, STARTUP_STATE = OFF);GOALTER EVENT SESSION newevt ON SERVER STATE = START;GONext, use this SQL query see the captured telemetry:SELECTevent_data.value('(@name)[1]', 'varchar(100)') AS event_name,event_data.value('(@timestamp)[1]', 'datetime2') AS [timestamp],event_data.value('(data[@name="model_name"]/value)[1]', 'nvarchar(200)') AS model_name,event_data.value('(data[@name="phase_name"]/value)[1]', 'nvarchar(100)') AS phase,event_data.value('(data[@name="message"]/value)[1]', 'nvarchar(max)') AS message,event_data.value('(data[@name="request_id"]/value)[1]', 'nvarchar(max)') AS session_id,event_data.value('(data[@name="error_code"]/value)[1]', 'bigint') AS error_codeFROM (SELECT CAST(target_data AS XML) AS target_dataFROM sys.dm_xe_sessions AS sJOIN sys.dm_xe_session_targets AS tON s.address = t.event_session_addressWHERE s.name = 'newevt'AND t.target_name = 'ring_buffer') AS dataCROSS APPLY target_data.nodes('//RingBufferTarget/event') AS XEvent(event_data);Clean upTo remove the external model object, run the following SQL:DROP EXTERNAL MODEL myLocalOnnxModel;To remove the directory permissions, run the following PowerShell commands:$Acl.RemoveAccessRule($AccessRule)Set-Acl -Path $AIExtPath -AclObject $AclFinally, delete the C:/onnx_runtime directory.