When getting aCannot query over table (...) without a filter over column(s) (...), the re-raising happening gobbles up the error message
and the context is lost.

This may or may not be the right fix, but clearly highlights the issue
ofself._query_job.errors beingNone in that particular context.
When that is the case, the only context available is that of
DatabaseError without any details which clearly isn't enough detail.

After this fix is applied (wrapping the exception into another exception) both stack traces are shown:  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/job.py", line 2685, in result    super(QueryJob, self).result(timeout=timeout)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/job.py", line 697, in result    return super(_AsyncJob, self).result(timeout=timeout)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/future/polling.py", line 115, in result    self._blocking_poll(timeout=timeout)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/job.py", line 2659, in _blocking_poll    super(QueryJob, self)._blocking_poll(timeout=timeout)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/future/polling.py", line 94, in _blocking_poll    retry_(self._done_or_raise)()  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/retry.py", line 260, in retry_wrapped_func    on_error=on_error,  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/retry.py", line 177, in retry_target    return target()  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/future/polling.py", line 73, in _done_or_raise    if not self.done():  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/job.py", line 2647, in done    location=self.location)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/client.py", line 584, in _get_query_results    retry, method='GET', path=path, query_params=extra_params)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/client.py", line 336, in _call_api    return call()  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/retry.py", line 260, in retry_wrapped_func    on_error=on_error,  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/api_core/retry.py", line 177, in retry_target    return target()  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/_http.py", line 293, in api_request    raise exceptions.from_http_response(response)google.api_core.exceptions.BadRequest: 400 GET https://www.googleapis.com/bigquery/v2/projects/fsql-production/queries/6ed337a4-e23c-4634-ba94-15254648bdfb?maxResults=0&location=US: Cannot query over table 'fsql-production.records.routes_stream' without a filter over column(s) 'created_at' that can be used for partition eliminationDuring handling of the above exception, another exception occurred:Traceback (most recent call last):  File "/home/mbeauchemin/incubator-superset/superset/sql_lab.py", line 185, in execute_sql    db_engine_spec.execute(cursor, query.executed_sql, async_=True)  File "/home/mbeauchemin/incubator-superset/superset/db_engine_specs.py", line 376, in execute    cursor.execute(query)  File "/home/mbeauchemin/incubator-superset/env/lib/python3.4/site-packages/google/cloud/bigquery/dbapi/cursor.py", line 157, in execute    raise exceptions.DatabaseError(self._query_job.errors or e)google.cloud.bigquery.dbapi.exceptions.DatabaseError: 400 GET https://www.googleapis.com/bigquery/v2/projects/fsql-production/queries/6ed337a4-e23c-4634-ba94-15254648bdfb?maxResults=0&location=US: Cannot query over table 'fsql-production.records.routes_stream' without a filter over column(s) 'created_at' that can be used for partition elimination

[bigquery] fix swallowed error message

a0fda13

When getting a "Cannot query over table (...) without a filter overcolumn(s) (...)", the re-raising happening gobbles up the error messageand the context is lost.This may or may not be the right fix, but clearly highlights the issueof `self._query_job.errors` being `None` in that particular context.When that is the case, the only context available is that of`DatabaseError` without any details which clearly isn't enough detail.It seems like wrapping the exception into another exception works asexpected and shows both stack traces as shown here:

mistercrunch requested a review fromtheacodes as acode owner

October 4, 2018 19:12

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sumedhsakdeo commentedOct 4, 2018

Looks great. CC:@tswast

tseaver changed the title~~[bigquery] fix swallowed error message~~BigQuery: fix swallowed error message

Oct 5, 2018

tseaver added the api: bigqueryIssues related to the BigQuery API. label

Oct 5, 2018

tseaver suggested changes

Oct 5, 2018

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bigquery/google/cloud/bigquery/dbapi/cursor.py Outdated

		exceptgoogle.cloud.exceptions.GoogleCloudError:
		raiseexceptions.DatabaseError(self._query_job.errors)
		exceptgoogle.cloud.exceptions.GoogleCloudErrorase:
		raiseexceptions.DatabaseError(self._query_job.errorsore)

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Pass just the exception to DatabaseError

d52c87f

The errors on the job resource are mostly redundant with the exception information.

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googlebot commentedOct 10, 2018

CLAs look good, thanks!

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