schema built when creating a view in bigquery

[jeremyjamesmitchell]

Calling create on a table with view_query set fails, as _build_resource sets the schema. Running

new_table = dataset.table('test_view')
table.view_query = query_string
new_table.create()

gives the following error:

BadRequest: 400 {
 "error": {
 "errors": [
 {
 "domain": "global",
 "reason": "invalid",
 "message": "Schema field shouldn't be used as input with a view"
 }
 ],
 "code": 400,
 "message": "Schema field shouldn't be used as input with a view"
 }
}

One fix that works is only setting schema if view_query is None in _build_resource in gcloud/bigquery/table.py, e.g.:

 def _build_resource(self):
 """Generate a resource for ``create`` or ``update``."""
 resource = {
 'tableReference': {
 'projectId': self._dataset.project,
 'datasetId': self._dataset.name,
 'tableId': self.name},
 }
 if self.description is not None:
 resource['description'] = self.description

 if self.expires is not None:
 value = _millis_from_datetime(self.expires)
 resource['expirationTime'] = value

 if self.friendly_name is not None:
 resource['friendlyName'] = self.friendly_name

 if self.location is not None:
 resource['location'] = self.location

 if self.view_query is not None:
 view = resource['view'] = {}
 view['query'] = self.view_query
 else:
 resource['schema'] = {'fields': _build_schema_resource(self._schema)}

 return resource

[tseaver]

Thanks for the detailed report!