Translate SQL queries with the translation API

This document describes how to use the translation API in BigQuery to translate scripts written in other SQL dialects into GoogleSQL queries. The translation API can simplify the process of migrating workloads to BigQuery.

Before you begin

Before you submit a translation job, complete the following steps:

Ensure that you have all the required permissions.
Enable the BigQuery Migration API.
Collect the source files containing the SQL scripts and queries to be translated.
Upload the source files to Cloud Storage.

Required permissions

To get the permissions that you need to create translation jobs using the translation API, ask your administrator to grant you the MigrationWorkflow Editor (roles/bigquerymigration.editor) IAM role on the parent resource. For more information about granting roles, see Manage access.

This predefined role contains the permissions required to create translation jobs using the translation API. To see the exact permissions that are required, expand the Required permissions section:

Required permissions

The following permissions are required to create translation jobs using the translation API:

bigquerymigration.workflows.create
bigquerymigration.workflows.get

You might also be able to get these permissions with custom roles or other predefined roles.

Enable the BigQuery Migration API

If your Google Cloud CLI project was created before February 15, 2022, enable the BigQuery Migration API as follows:

In the Google Cloud console, go to the BigQuery Migration API page.

Go to BigQuery Migration API
Click Enable.

Upload input files to Cloud Storage

If you want to use the Google Cloud console or the BigQuery Migration API to perform a translation job, you must upload the source files containing the queries and scripts you want to translate to Cloud Storage. You can also upload any metadata files or configuration YAML files to the same Cloud Storage bucket containing the source files. For more information about creating buckets and uploading files to Cloud Storage, see Create buckets and Upload objects from a filesystem.

Supported task types

The translation API can translate the following SQL dialects into GoogleSQL:

Amazon Redshift SQL - Redshift2BigQuery_Translation
Apache HiveQL and Beeline CLI - HiveQL2BigQuery_Translation
Apache Spark SQL - SparkSQL2BigQuery_Translation
Azure Synapse T-SQL - AzureSynapse2BigQuery_Translation
IBM Netezza SQL and NZPLSQL - Netezza2BigQuery_Translation
MySQL SQL - MySQL2BigQuery_Translation
Oracle SQL, PL/SQL, Exadata - Oracle2BigQuery_Translation
PostgreSQL SQL - Postgresql2BigQuery_Translation
Presto or Trino SQL - Presto2BigQuery_Translation
Snowflake SQL - Snowflake2BigQuery_Translation
SQL Server T-SQL - SQLServer2BigQuery_Translation
Teradata and Teradata Vantage - Teradata2BigQuery_Translation
Vertica SQL - Vertica2BigQuery_Translation

The translation API also supports the following translation tasks:

Translate Oracle SQL to PostgreSQL SQL - Oracle2Postgresql_Translation

Locations

The translation API is available in the following processing locations:

	Region description	Region name	Details
Asia Pacific
	Tokyo	`asia-northeast1`
	Mumbai	`asia-south1`
	Singapore	`asia-southeast1`
	Sydney	`australia-southeast1`
Europe
	EU multi-region	`eu`
	Warsaw	`europe-central2`
	Finland	`europe-north1`	Low CO₂
	Madrid	`europe-southwest1`
	Belgium	`europe-west1`	Low CO₂
	London	`europe-west2`	Low CO₂
	Frankfurt	`europe-west3`	Low CO₂
	Netherlands	`europe-west4`
	Zürich	`europe-west6`	Low CO₂
	Paris	`europe-west9`	Low CO₂
	Turin	`europe-west12`
Americas
	São Paulo	`southamerica-east1`	Low CO₂
	US multi-region	`us`
	Iowa	`us-central1`	Low CO₂
	South Carolina	`us-east1`
	Northern Virginia	`us-east4`
	Columbus, Ohio	`us-east5`
	Dallas	`us-south1`
	Oregon	`us-west1`	Low CO₂
	Los Angeles	`us-west2`
	Salt Lake City	`us-west3`

Submit a translation job

To submit a translation job using the translation API, use the projects.locations.workflows.create method and supply an instance of the MigrationWorkflow resource with a supported task type.

Example: Create a batch translation

The following curl command creates a batch translation job where the input and output files are stored in Cloud Storage. The source_target_mapping field contains a list that maps the source literal entries to an optional relative path for the target output.

curl -d "{
  \"tasks\": {
      string: {
        \"type\": \"TYPE\",
        \"translation_details\": {
            \"target_base_uri\": \"TARGET_BASE\",
            \"source_target_mapping\": {
              \"source_spec\": {
                  \"base_uri\": \"BASE\"
              }
            },
        }
      }
  }
  }" \
  -H "Content-Type:application/json" \
  -H "Authorization: Bearer TOKEN" -X POST https://bigquerymigration.googleapis.com/v2alpha/projects/PROJECT_ID/locations/LOCATION/workflows

Replace the following:

TYPE: the task type of the translation, which determines the source and target dialect.
TARGET_BASE: the base URI for all translation outputs.
BASE: the base URI for all files read as sources for translation.
TOKEN: the token for authentication. To generate a token, use the gcloud auth print-access-token command or the OAuth 2.0 playground (use the scope https://www.googleapis.com/auth/cloud-platform).
PROJECT_ID: the project to process the translation.
LOCATION: the location where the job is processed.

The preceding command returns a response that includes a workflow ID written in the format projects/PROJECT_ID/locations/LOCATION/workflows/WORKFLOW_ID.

Example: Create an interactive translation job with string literal inputs and outputs

The following curl command creates a translation job with string literal inputs and outputs. The source_target_mapping field contains a list that maps the source directories to an optional relative path for the target output.

curl -d "{
  \"tasks\": {
      string: {
        \"type\": \"TYPE\",
        \"translation_details\": {
        \"source_target_mapping\": {
            \"source_spec\": {
              \"literal\": {
              \"relative_path\": \"PATH\",
              \"literal_string\": \"STRING\"
              }
            }
        },
        \"target_return_literals\": \"TARGETS\",
        }
      }
  }
  }" \
  -H "Content-Type:application/json" \
  -H "Authorization: Bearer TOKEN" -X POST https://bigquerymigration.googleapis.com/v2alpha/projects/PROJECT_ID/locations/LOCATION/workflows

Replace the following:

TYPE: the task type of the translation, which determines the source and target dialect.
PATH: the identifier of the literal entry, similar to a filename or path.
STRING: string of literal input data (for example, SQL) to be translated.
TARGETS: the expected targets that the user wants to be directly returned in the response in the literal format. These should be in the target URI format (for example, GENERATED_DIR + target_spec.relative_path + source_spec.literal.relative_path). Anything not in this list is not returned in the response. The generated directory, GENERATED_DIR for general SQL translations is sql/.
TOKEN: the token for authentication. To generate a token, use the gcloud auth print-access-token command or the OAuth 2.0 playground (use the scope https://www.googleapis.com/auth/cloud-platform).
PROJECT_ID: the project to process the translation.
LOCATION: the location where the job is processed.

The preceding command returns a response that includes a workflow ID written in the format projects/PROJECT_ID/locations/LOCATION/workflows/WORKFLOW_ID.

Explore the translation output

After running the translation job, retrieve the results by specifying the translation job workflow ID using the following command:

curl \
-H "Content-Type:application/json" \
-H "Authorization:Bearer TOKEN" -X GET https://bigquerymigration.googleapis.com/v2alpha/projects/PROJECT_ID/locations/LOCATION/workflows/WORKFLOW_ID

Replace the following:

TOKEN: the token for authentication. To generate a token, use the gcloud auth print-access-token command or the OAuth 2.0 playground (use the scope https://www.googleapis.com/auth/cloud-platform).
PROJECT_ID: the project to process the translation.
LOCATION: the location where the job is processed.
WORKFLOW_ID: the ID generated when you create a translation workflow.