BigQuery bq command - load only if table is empty or doesn't exist

Question

I'm executing a load command with bq, e.g:

bq load ds.table gs://mybucket/data.csv dt:TIMESTAMP,f1:INTEGER

I would like to load the data only if the table is empty or doesn't exist.

Is it possible?

EDIT:

Basically I would like the WRITE_EMPTY API option via the bq command line tool:

https://cloud.google.com/bigquery/docs/reference/v2/jobs#configuration.load.writeDisposition

If the table already exists and contains data, a 'duplicate' error is returned in the job result.

Answer 1

If you go check bq.py, that has the source code for the BigQuery CLI, you'll find out that the _Load() method doesn't implement an option for the WRITE_EMPTY API option. It's either the default WRITE_APPEND or the optional WRITE_TRUNCATE.

As you indicate, the API does support WRITE_EMPTY - if you want to see this as an option on the CLI, you can submit a feature request at https://code.google.com/p/google-bigquery/issues/list?q=label:Feature-Request

Answer 2

You can use the BQ command-line tool.

Get Table Information

bq show <project_id>:<dataset_id>.<table_id>

List tables

 bq ls [project_id:][dataset_id]