The problem statement is to Load the Google Spanner data from Google BigQuery, The size of BigQuery table is huge and we need to come up with the effective solution
I tried exploring various options but not getting the solution
Google provides many templates to move data from one storage system to another. You can find them at https://cloud.google.com/dataflow/docs/guides/templates/provided-templates
None of these are "BigQuery to Cloud Spanner" but they are very similar. The templates are open source, so you can use them as examples. You can find the source code for the templates at https://github.com/GoogleCloudPlatform/DataflowTemplates