Exception not thrown on syntax error

Environment details

• OS: MacOS
• Node.js version: 12.18
• npm version: 6.14.4
• @google-cloud/bigquery version: 5.3.0

Steps to reproduce

  it("throws on bigquery syntax error", async () => {
    const bq = new BigQuery({ projectId: "REDACTED" })

    const [job] = await bq.createQueryJob({
      query: `DECLARE foo DEFAULT ( SELECT 1 );
      SELECT 1 FROM XYZ`,
      timeoutMs: 5000,
      location: "US"
    })

    const [rows] = await job.getQueryResults()

    assert.strictEqual(rows.length, 0)
  })

Expected result:

Invalid value: Table name “XYZ” missing dataset while no default dataset is set in the request. at [2:1]

Actual result No exception is thrown, rows.length = 0

[steffnay]

The issue here is that scripting statements like this generate child jobs for each statement. When you call job.getQueryResults using the original parent job, what’s returned is the result of the last statement that executed. So, in the case of your example, it returns the empty results from the DECLARE statement’s execution.

To obtain the results of all statements in the script, you must enumerate the child jobs and call jobs.getQueryResults on each of them. You can access the list of child jobs by setting the parentJobId option in a bigquery.getJobs call.

Here is how you would access the error from your example:

 const bq = new BigQuery({ projectId: "REDACTED" });

 [job] = await bq.createQueryJob({
   query: 
   `DECLARE foo DEFAULT ( SELECT 1 );
   SELECT 1 FROM XYZ`,
   timeoutMs: 5000,
   location: "US"
 });

 // Must still wait for parent job to complete before accessing child jobs
 const [rows] = await job.getQueryResults();

 const [childJobs] = await bq.getJobs({parentJobId: job.id});

 for (const job of childJobs) {
   console.log('Job: ', job.id);
   console.log('Error: ', job.metadata.errorResult);
 }

// Output:
//
// Job:  script_job_123...
// Error:  { reason: 'invalid',
//   location: 'xyz',
//   message: 'Table name "xyz" missing dataset while no default dataset is set in the request.' }
//
// Job:  script_job_678...
// Error:  undefined

Documentation for this concept is here.

[ro8inmorgan]

I actually have a similar problem but not with table name but with an incorrect field name. There’s no error thrown, just an empty result. In the Google Console the job did error.