Database Reference
In-Depth Information
a list operation immediately afterward, you may not see your new dataset
in that list right away. With the exception of
Datasets.list()
and
Tables.list()
, all operations in the BigQuery API are guaranteed to be
consistent.
The list operation doesn't return the full Dataset resource; it returns only the
dataset reference fields. If you need to see the full resource—for example, if
you want to see the dataset ACLs—you need to call
Datasets.get()
on
the dataset you want to read.
Note that
Datasets.list()
returns only datasets that you have access to.
BigQuery must do an access check for each dataset, which is a somewhat
expensive operation. For this reason, the total number of datasets in the
collection is not returned. This lets BigQuery return a page of results without
having to do the access checks on all the datasets in the project. It can
just return when it has found enough datasets to satisfy the
maxResults
parameter. The way to tell whether more datasets are available is that the
response contains a
pageToken
field, which you can then use to page
through the results.
Following is a
curl
transcript showing a
Datasets.list()
request that
is limited to the first result:
$
curl -H "$(python auth.py)" \
"${DATASETS_URL}?maxResults=1"
{
"nextPageToken": "scratch",
"datasets": [
{
"kind": "bigquery#dataset",
"id": "bigquery-e2e:scratch",
"datasetReference": {
"datasetId": "scratch",
"projectId": "bigquery-e2e"
}
}
]
}
