[Feature Request]: Update the default behaviour in `BigQueryIO.Write.Method.DEFAULT` to `STORAGE_API_AT_LEAST_ONCE`

[borjavb]

What would you like to happen?

The default behaviour of BigQueryIO.Write.Method for unbounded collections is to use STREAMING_INSERTS, which is now categorised as legacy .

Two new methods STORAGE_API_AT_LEAST_ONCE and STORAGE_WRITE_API are available, being STORAGE_API_AT_LEAST_ONCE the closest in the underlying semantics to STREAMING_INSERTS (best effort deduplication but no guarantees of only once). Using the storage API is also cheaper than the legacy streaming inserts by 50%, with the first 2TB free..

Should the default method point to STORAGE_API_AT_LEAST_ONCE instead of keep using STREAMING_INSERTS?

Issue Priority

Priority: 3 (nice-to-have improvement)

Issue Components

• Component: Python SDK
• Component: Java SDK
• Component: Go SDK
• Component: Typescript SDK
• Component: IO connector
• Component: Beam YAML
• Component: Beam examples
• Component: Beam playground
• Component: Beam katas
• Component: Website
• Component: Spark Runner
• Component: Flink Runner
• Component: Samza Runner
• Component: Twister2 Runner
• Component: Hazelcast Jet Runner
• Component: Google Cloud Dataflow Runner

[liferoad]

We usually do not change the default. For this case, the recommended way is to use Managed IO once we onboard BigQuery IO to it.

[Abacn]

This Issue is marked as Beam 3 - Milestone 1: No Code and ML focus. Please help us burning down the open blocker tasks.

• If this issue is solved, close it. If it is obsolete, close as not planned. If it is no longer necessary for Beam 3, move it out of the Milestone.

• If the work is pending, please be reminded that Milestone 1 is targeted for completion by Dec 30, 2025

• If this issue involves multiple milestones (e.g. remove a public API should first mark it as deprecated, scoped in Milestone 1; then finally remove it in Beam 3 release candidate, scoped in Milestone 3) and Milestone 1 portion has completed, consider move the Issue to Milestone 3.