# Manage materialized view replicas
This document describes how to manage materialized view replicas in
BigQuery.
BigQuery management of materialized view replicas includes
the following operations:
- [List materialized view replicas](https://docs.cloud.google.com/bigquery/docs/materialized-view-replicas-manage#list)
- [Get information about materialized view replicas](https://docs.cloud.google.com/bigquery/docs/materialized-view-replicas-manage#get-info)
- [Delete materialized view replicas](https://docs.cloud.google.com/bigquery/docs/materialized-view-replicas-manage#delete)
For more information about materialized view replicas, see the following:
- [Materialized view replicas](https://docs.cloud.google.com/bigquery/docs/load-data-using-cross-cloud-transfer#materialized_view_replicas)
- [Create materialized view replicas](https://docs.cloud.google.com/bigquery/docs/load-data-using-cross-cloud-transfer#create)
## Before you begin
Grant Identity and Access Management (IAM) roles that give users the necessary permissions
to perform each task in this document. The permissions required to perform a
task (if any) are listed in the "Required permissions" section of the task.
## List materialized view replicas
You can list materialized view replicas through the Google Cloud console.
### Required permissions
To list materialized view replicas in a dataset, you need the
`bigquery.tables.list` IAM permission.
Each of the following predefined IAM roles includes the
permissions that you need in order to list materialized view replicas in
a dataset:
- `roles/bigquery.user`
- `roles/bigquery.metadataViewer`
- `roles/bigquery.dataViewer`
- `roles/bigquery.dataOwner`
- `roles/bigquery.dataEditor`
- `roles/bigquery.admin`
For more information on IAM roles and permissions in
IAM, see [Predefined roles and permissions](https://docs.cloud.google.com/bigquery/docs/access-control).
To list the materialized view replicas in a dataset:
1. In the left pane, click **Explorer**:
If you don't see the left pane, click **Expand left pane** to open the pane.
2. In the **Explorer** pane, expand your project, click **Datasets**, and
then click the dataset.
3. Click **Overview \> Tables** . Scroll through the list to see the tables in the
dataset. Tables, views, and materialized views are identified by different
values in the **Type** column. Materialized view replicas have the same value
as materialized views.
## Get information about materialized view replicas
You can get information about a materialized view replica by using SQL, the
bq command-line tool, or the BigQuery API.
### Required permissions
To query information about a materialized view replica, you need the following
Identity and Access Management (IAM) permissions:
- `bigquery.tables.get`
- `bigquery.tables.list`
- `bigquery.routines.get`
- `bigquery.routines.list`
Each of the following predefined IAM roles includes the preceding
permissions:
- `roles/bigquery.metadataViewer`
- `roles/bigquery.dataViewer`
- `roles/bigquery.admin`
For more information about BigQuery permissions, see
[Access control with IAM](https://docs.cloud.google.com/bigquery/docs/access-control).
To get information about a materialized view replica, including the source
[materialized view](https://docs.cloud.google.com/bigquery/docs/materialized-views-intro):
### SQL
To get information about materialized view replicas, query the
[`INFORMATION_SCHEMA.TABLES` view](https://docs.cloud.google.com/bigquery/docs/information-schema-tables):
1. In the Google Cloud console, go to the **BigQuery** page.
[Go to BigQuery](https://console.cloud.google.com/bigquery)
2. In the query editor, enter the following statement:
```googlesql
SELECT * FROM PROJECT_ID.DATASET_ID.INFORMATION_SCHEMA.TABLES
WHERE table_type = 'MATERIALIZED VIEW';
```
Replace the following:
- `PROJECT_ID`: the name of the project that contains the materialized view replicas
- `DATASET_ID`: the name of the dataset that contains the materialized view replicas
3. Click **Run**.
For more information about how to run queries, see [Run an interactive query](https://docs.cloud.google.com/bigquery/docs/running-queries#queries).
### bq
Use the
[`bq show` command](https://docs.cloud.google.com/bigquery/docs/reference/bq-cli-reference#bq_show):
```bash
bq show --project=project_id --format=prettyjson dataset.materialized_view_replica
```
Replace the following:
- project_id: the project ID. You only need to include this flag to get information about a materialized view replica in a different project than the default project.
- dataset: the name of the dataset that contains the materialized view replica.
- materialized_view_replica: the name of the materialized view replica that you want information about.
Example:
Enter the following command to show information about the materialized
view replica `my_mv_replica` in the `report_views` dataset in the
`myproject` project.
bq show --project=myproject --format=prettyjson report_views.my_mv_replica
### API
To get materialized view replica information by using the API, call the
[`tables.get`](https://docs.cloud.google.com/bigquery/docs/reference/rest/v2/tables/get) method.
## Delete materialized view replicas
You can delete a materialized view replica through the Google Cloud console.
> [!CAUTION]
> **Caution:** Deleting a materialized view replica can't be undone.
### Required permissions
To delete materialized view replicas, you need the `bigquery.tables.delete`
IAM permission.
Each of the following predefined IAM roles includes the
permissions that you need in order to delete a materialized view replica:
- `bigquery.dataEditor`
- `bigquery.dataOwner`
- `bigquery.admin`
For more information about
BigQuery Identity and Access Management (IAM), see
[Predefined roles and permissions](https://docs.cloud.google.com/bigquery/docs/access-control).
1. In the left pane, click **Explorer**:
2. In the **Explorer** pane, expand your project, click **Datasets**, and
then click the dataset.
3. Click **Overview \> Tables**, and then click the materialized view replica.
4. In the details pane, click **More \> Delete**.
5. In the **Delete materialized view?** dialog, type `delete` into the field,
and then click **Delete**.