Process documents with the ML.PROCESS_DOCUMENT function

This document describes how to use the ML.PROCESS_DOCUMENT function with a remote model to extract useful insights from documents in an object table.

Supported locations

You must create the remote model used in this procedure in either the US or EU multi-region. You must run the ML.PROCESS_DOCUMENT function in the same region as the remote model.

Required permissions

• To create a Document AI processor, you need the following role:

  • roles/documentai.editor

• To create a connection, you need membership in the following role:

  • roles/bigquery.connectionAdmin

• To create the model using BigQuery ML, you need the following permissions:

  • bigquery.jobs.create
  • bigquery.models.create
  • bigquery.models.getData
  • bigquery.models.updateData
  • bigquery.models.updateMetadata

• To run inference, you need the following permissions:

  • bigquery.tables.getData on the object table
  • bigquery.models.getData on the model
  • bigquery.jobs.create

Before you begin

1. Sign in to your Google Cloud account. If you're new to Google Cloud, create an account to evaluate how our products perform in real-world scenarios. New customers also get $300 in free credits to run, test, and deploy workloads.

2. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

3. Make sure that billing is enabled for your Google Cloud project.

4. Enable the BigQuery, BigQuery Connection API, and Document AI APIs.

   Enable the APIs

5. In the Google Cloud console, on the project selector page, select or create a Google Cloud project.

   Note: If you don't plan to keep the resources that you create in this procedure, create a project instead of selecting an existing project. After you finish these steps, you can delete the project, removing all resources associated with the project.

   Go to project selector

6. Make sure that billing is enabled for your Google Cloud project.

7. Enable the BigQuery, BigQuery Connection API, and Document AI APIs.

   Enable the APIs

Create a processor

Create a processor in Document AI to process the documents. The processor must be of a supported type.

Create a connection

Create a cloud resource connection and get the connection's service account.

Select one of the following options:

Console

1. Go to the BigQuery page.

   Go to BigQuery

2. To create a connection, click Add, and then click Connections to external data sources.

3. In the Connection type list, select Vertex AI remote models, remote functions and BigLake (Cloud Resource).

4. In the Connection ID field, enter a name for your connection.

5. Click Create connection.

6. Click Go to connection.

7. In the Connection info pane, copy the service account ID for use in a later step.

bq

1. In a command-line environment, create a connection:

   bq mk --connection --location=REGION --project_id=PROJECT_ID \
       --connection_type=CLOUD_RESOURCE CONNECTION_ID

   The --project_id parameter overrides the default project.

   Replace the following:

   • REGION: your connection region
   • PROJECT_ID: your Google Cloud project ID
   • CONNECTION_ID: an ID for your connection

   When you create a connection resource, BigQuery creates a unique system service account and associates it with the connection.

   Troubleshooting: If you get the following connection error, update the Google Cloud SDK:

   Flags parsing error: flag --connection_type=CLOUD_RESOURCE: value should be one of...
   

2. Retrieve and copy the service account ID for use in a later step:

   bq show --connection PROJECT_ID.REGION.CONNECTION_ID

   The output is similar to the following:

   name                          properties
   1234.REGION.CONNECTION_ID     {"serviceAccountId": "[e-mail]"}
   

Terraform

Append the following section into your main.tf file.

 ## This creates a cloud resource connection.
 ## Note: The cloud resource nested object has only one output only field - serviceAccountId.
 resource "google_bigquery_connection" "connection" {
    connection_id = "CONNECTION_ID"
    project = "PROJECT_ID"
    location = "REGION"
    cloud_resource {}
}        

Replace the following:

• CONNECTION_ID: an ID for your connection
• PROJECT_ID: your Google Cloud project ID
• REGION: your connection region

Grant access to the service account

Select one of the following options:

Console

1. Go to the IAM & Admin page.

   Go to IAM & Admin

2. Click Grant Access.

   The Add principals dialog opens.

3. In the New principals field, enter the service account ID that you copied earlier.

4. In the Select a role field, select Document AI, and then select Document AI Viewer.

5. Click Add another role.

6. In the Select a role field, select Cloud Storage, and then select Storage Object Viewer.

7. Click Save.

gcloud

Use the gcloud projects add-iam-policy-binding command:

gcloud projects add-iam-policy-binding 'PROJECT_NUMBER' --member='serviceAccount:MEMBER' --role='roles/documentai.viewer' --condition=None
gcloud projects add-iam-policy-binding 'PROJECT_NUMBER' --member='serviceAccount:MEMBER' --role='roles/storage.objectViewer' --condition=None

Replace the following:

• PROJECT_NUMBER: your project number.
• MEMBER: the service account ID that you copied earlier.

Failure to grant the permission results in a Permission denied error.

Note: If you create the processor in a different project than the Cloud Storage bucket used by the object table, grant the service account Identity and Access Management (IAM) roles as follows:

• Grant the service account the Document AI Viewer role in the project that contains the processor.
• Grant the service account the Storage Object Viewer role in the project that contains the Cloud Storage bucket.

Create a dataset

Create a dataset to contain the model and the object table. You must create the dataset, the connection and the document processor in the same region.

Create a model

Create a remote model with a REMOTE_SERVICE_TYPE of CLOUD_AI_DOCUMENT_V1:

CREATE OR REPLACE MODEL
`PROJECT_ID.DATASET_ID.MODEL_NAME`
REMOTE WITH CONNECTION `PROJECT_ID.REGION.CONNECTION_ID`
OPTIONS (
  REMOTE_SERVICE_TYPE = 'CLOUD_AI_DOCUMENT_V1',
  DOCUMENT_PROCESSOR = 'PROCESSOR_ID'
);

Replace the following:

• PROJECT_ID: your project ID.
• DATASET_ID: the ID of the dataset to contain the model.
• MODEL_NAME: the name of the model.
• REGION: the region used by the connection.
• CONNECTION_ID: the connection ID—for example, myconnection.

  When you view the connection details in the Google Cloud console, the connection ID is the value in the last section of the fully qualified connection ID that is shown in Connection ID—for example projects/myproject/locations/connection_location/connections/myconnection.

• PROCESSOR_ID: the document processor ID. To find this value, view the processor details, and then look at the ID row in the Basic Information section.

Important: You must specify the project ID for the connection even if the connection is in the default project.

To see the model output columns, click Go to model in the query result after the model is created. The output columns are shown in the Labels section of the Schema tab.

Create an object table

Create an object table over a set of documents in Cloud Storage. The documents in the object table must be of a supported type.

Process documents

Process all the documents with the ML.PROCESS_DOCUMENT:

SELECT *
FROM ML.PROCESS_DOCUMENT(
  MODEL `PROJECT_ID.DATASET_ID.MODEL_NAME`,
  TABLE `PROJECT_ID.DATASET_ID.OBJECT_TABLE_NAME`
);

Replace the following:

• PROJECT_ID: your project ID.
• DATASET_ID: the ID of the dataset that contains the model.
• MODEL_NAME: the name of the model.
• OBJECT_TABLE_NAME: the name of the object table that contains the URIs of the documents to process.

Alternatively, process some of the documents with the ML.PROCESS_DOCUMENT:

SELECT *
FROM ML.PROCESS_DOCUMENT(
  MODEL `PROJECT_ID.DATASET_ID.MODEL_NAME`,
  (SELECT *
  FROM `PROJECT_ID.DATASET_ID.OBJECT_TABLE_NAME`
  WHERE FILTERS
  LIMIT NUM_DOCUMENTS
  )
);

Replace the following:

• PROJECT_ID: your project ID.
• DATASET_ID: the ID of the dataset that contains the model.
• MODEL_NAME: the name of the model.
• OBJECT_TABLE_NAME: the name of the object table that contains the URIs of the documents to process.
• FILTERS: conditions to filter out the documents you want to process on the object table columns.
• NUM_DOCUMENTS: the max number of documents you want to process.

Examples

Example 1

The following example uses the expense parser to process the documents represented by the documents table:

SELECT *
FROM ML.PROCESS_DOCUMENT(
  MODEL `myproject.mydataset.expense_parser`,
  TABLE `myproject.mydataset.documents`
);

This query returns the parsed expense reports, including the currency, total amount, receipt date, and line items on the expense reports. The ml_process_document_result column contains the raw output of the expense parser, and the ml_process_document_status column contains any errors returned by the document processing.

Example 2

The following example shows how to filter the object table to choose which documents to process, and then write the results to a new table:

CREATE TABLE `myproject.mydataset.expense_details`
AS
SELECT uri, content_type, receipt_date, purchase_time, total_amount, currency
FROM
  ML.PROCESS_DOCUMENT(
    MODEL `myproject.mydataset.expense_parser`,
    (SELECT * FROM `myproject.mydataset.expense_reports`
    WHERE uri LIKE '%restaurant%'));

What's next

• For information about model inference in BigQuery ML, see Model inference overview.
• For information about the supported SQL statements and functions for each model type, see End-to-end user journey for each model.