Database Reference
In-Depth Information
a lot of data. What's more, there is a good chance you don't care about
the actual query text, so most of what you're reading isn't useful. BigQuery
supports three mechanisms to help reduce the amount of data returned and
to focus on the interesting data: projections, field restrictions, and ETags.
Projections
Projections are predefined views of a resource that include only a subset of
the resource's fields. The Jobs collection is the only collection in BigQuery
that supports projection. It defines two projections:
full
and
minimal
.
The
full
projection returns the entire job, which may include a lot of
data—the full text of queries, full table schemas, and so on. The
minimal
projection, on the other hand, omits a lot of potentially expensive fields and
just returns the fields that are likely to be more interesting—the job status,
the statistics, and so on. When listing jobs, the default projection that is
returned is the minimal one. If you want to see the full projection, you can
specify
projection=full
in the URL query string.
Here is an example that returns the minimal projection of a single job:
$
JOBS_URL=${PROJECT_URL}/jobs
$
curl -H "$(python auth.py)" \
"${JOBS_URL}?maxResults=1&projection=minimal"
{
"kind": "bigquery#jobList",
"etag": "\"yBc8hy8wJ370nDaoIj0ElxNcWUg/
UakzbU_RhC8kGP0ve9SOqAWE6Ls\"",
"nextPageToken": "1374677424654-…",
"jobs": [
{
"id":
"bigquery-e2e:bqjob_r1ef2a0ae815fa433_000001401128cb0b_1",
"kind": "bigquery#job",
"jobReference": {
"projectId": "bigquery-e2e",
"jobId":
"bqjob_r1ef2a0ae815fa433_000001401128cb0b_1"
},
"state": "DONE",
