SCHEMATA view

The INFORMATION_SCHEMA.SCHEMATA view provides information about the datasets in a project or region. The view returns one row for each dataset.

Before you begin

To query the SCHEMATA view for dataset metadata, you need the bigquery.datasets.get Identity and Access Management (IAM) permission at the project level.

Each of the following predefined IAM roles includes the permissions that you need in order to get the SCHEMATA view:

roles/bigquery.admin
roles/bigquery.dataEditor
roles/bigquery.dataOwner
roles/bigquery.dataViewer

For more information about BigQuery permissions, see Access control with IAM.

Schema

When you query the INFORMATION_SCHEMA.SCHEMATA view, the query results contain one row for each dataset in the specified project.

The INFORMATION_SCHEMA.SCHEMATA view has the following schema:

Column name	Data type	Value
`CATALOG_NAME`	`STRING`	The name of the project that contains the dataset
`SCHEMA_NAME`	`STRING`	The dataset's name also referred to as the `datasetId`
`SCHEMA_OWNER`	`STRING`	The value is always `NULL`
`CREATION_TIME`	`TIMESTAMP`	The dataset's creation time
`LAST_MODIFIED_TIME`	`TIMESTAMP`	The dataset's last modified time
`LOCATION`	`STRING`	The dataset's geographic location
`DDL`	`STRING`	The `CREATE SCHEMA` DDL statement that can be used to create the dataset
`DEFAULT_COLLATION_NAME`	`STRING`	The name of the default collation specification if it exists; otherwise, `NULL`.

Scope and syntax

Queries against this view must include a region qualifier. If you do not specify a regional qualifier, metadata is retrieved from the US region. The following table explains the region scope for this view:

View Name	Resource scope	Region scope
`[PROJECT_ID.]INFORMATION_SCHEMA.SCHEMATA`	Project level	US region
[PROJECT_ID.]`region-REGION`.INFORMATION_SCHEMA.SCHEMATA	Project level	`REGION`

Replace the following:

Optional: PROJECT_ID: the ID of your Google Cloud project. If not specified, the default project is used.
REGION: any dataset region name. For example, `region-us`.

Note: You must use a region qualifier to query INFORMATION_SCHEMA views. The location of the query execution must match the region of the INFORMATION_SCHEMA view.

Example

-- Returns metadata for datasets in a region.
SELECT * FROM region-us.INFORMATION_SCHEMA.SCHEMATA;

Example

To run the query against a project other than your default project, add the project ID to the dataset in the following format:

`PROJECT_ID`.INFORMATION_SCHEMA.SCHEMATA

for example, `myproject`.INFORMATION_SCHEMA.SCHEMATA.

SELECT
  * EXCEPT (schema_owner)
FROM
  INFORMATION_SCHEMA.SCHEMATA;

The result is similar to the following. For readability, some columns are excluded from the result.

+----------------+---------------+---------------------+---------------------+------------+------------------------------------------+
|  catalog_name  |  schema_name  |    creation_time    | last_modified_time  |  location  |                   ddl                    |
+----------------+---------------+---------------------+---------------------+------------+------------------------------------------+
| myproject      | mydataset1    | 2018-11-07 19:50:24 | 2018-11-07 19:50:24 | US         | CREATE SCHEMA `myproject.mydataset1`     |
|                |               |                     |                     |            | OPTIONS(                                 |
|                |               |                     |                     |            |   location="us"                          |
|                |               |                     |                     |            | );                                       |
+----------------+---------------+---------------------+---------------------+------------+------------------------------------------+
| myproject      | mydataset2    | 2018-07-16 04:24:22 | 2018-07-16 04:24:22 | US         | CREATE SCHEMA `myproject.mydataset2`     |
|                |               |                     |                     |            | OPTIONS(                                 |
|                |               |                     |                     |            |   default_partition_expiration_days=3.0, |
|                |               |                     |                     |            |   location="us"                          |
|                |               |                     |                     |            | );                                       |
+----------------+---------------+---------------------+---------------------+------------+------------------------------------------+
| myproject      | mydataset3    | 2018-02-07 21:08:45 | 2018-05-01 23:32:53 | US         | CREATE SCHEMA `myproject.mydataset3`     |
|                |               |                     |                     |            | OPTIONS(                                 |
|                |               |                     |                     |            |   description="My dataset",              |
|                |               |                     |                     |            |   location="us"                          |
|                |               |                     |                     |            | );                                       |
+----------------+---------------+---------------------+---------------------+------------+------------------------------------------+