Knowledge Hub Technologies Google Bigtable
Bigtable

Google Bigtable as a wide-column NoSQL source or target. One connection maps to one instance. Bigtable participates in pipelines through Spark/Dataproc — there is currently no row-level ETL-Native executor.

Connection Fields

Source: GcpConnectorPlugin.ts (connector type GCP_BIGTABLE).

FieldRequiredDefaultNotes
bigtable_project_idYes
bigtable_instance_idYesOne connection maps to one instance.
auth_methodYesSERVICE_ACCOUNT_KEY · WORKLOAD_IDENTITY · APPLICATION_DEFAULT. Recommended: WORKLOAD_IDENTITY.
service_account_emailFor WORKLOAD_IDENTITY
bigtable_app_profileNodefault
bigtable_table_idNoTable to read/write.
bigtable_column_familyNoColumn family used for writes.
gcp_auth_refNoReuse credentials from another GCP connector.
service_account_key_json (secret)For SERVICE_ACCOUNT_KEY

Required IAM Roles

Schema Behaviour

Bigtable has no fixed schema. Metadata browsing (describeTable()) surfaces column families only — individual column qualifiers only exist per-row at read time and are not part of any discoverable schema.

Spark reads and writes use com.google.cloud.spark.bigtable:spark-bigtable_2.12:0.9.1.

Known Limitations

There is no ETL-Native row-level executor for Bigtable. ETL-Native support is limited to metadata browsing and connection testing — actual row read/write only happens through the Spark/Dataproc path.