is there a way we can stream Spanner table data to BQ? we have dataflow job that does truncate and load BQ table on periodically. But we want near real data to BQ, so looking for solution kind of Spanner backup in BQ in near realtime.
I have found this Feature Request related to your question. You can star it and comment in order to get further updates from the team in charge.
In addition, as a workaround you could export your data from Spanner to GCS, and then upload it into BigQuery.