Google BigQuery

Dremio supports connecting to Google BigQuery as an external source. The connector uses Google service account keys as the authentication method. To know more about creating service account keys, see Create and delete service account keys.

Requirements

To connect to Google BigQuery, you need:

• Google BigQuery
• Source configuration for authentication

Dremio Configuration

1. On the Datasets page, to the right of Sources in the left panel, click .

2. In the Add Data Source dialog, under Databases, select the source.

   The new source dialog box appears, which contains the following tabs:

   • General: Create a name for your database, specify the connection details, and set the authentication.
   • Advanced Options: (Optional) Set the advanced configuration options for your database.
   • Reflection Refresh: (Optional) Set a policy to control how often reflections are refreshed and expired.
   • Metadata: (Optional) Specify dataset handling and metadata refresh.
   • Privileges: (Optional) Add privileges for users or roles.

   Refer to the following sections for guidance on how to edit each tab.

General

To configure the source connection:

1. For Name, enter the name to identify the database in Dremio. The name cannot include the following special characters: /, :, [, or ].

2. For Host, enter the hostname or IP address for the Google BigQuery source.

3. For Port, enter the Google BigQuery port number. The default port is 443.

4. For Database, enter the service name of your database.

5. For Username, enter the database username.

6. For Password, choose an authentication method:

   • No Authentication: Dremio does not attempt to provide any authentication when connecting with the SQL pool.

   • Master Credentials: Dremio must provide a specified username and password in order to access the SQL pool.

     • For Username, enter the database username.
     • For Password, choose a method:

     • Dremio: Provide the database password in plain text. Dremio stores the password.

     • Azure Key Vault: Provide the URI for the Azure Key Vault secret that stores the Vertica password. The URI format is https://<vault_name>.vault.azure.net/secrets/<secret_name> (for example, https://myvault.vault.azure.net/secrets/mysecret).

       note

       To use Azure Key Vault as your application secret store, you must:

       • Deploy Dremio on Azure.

       • Complete the Requirements for Authenticating with Azure Key Vault.

       It is not necessary to restart the Dremio coordinator when you rotate secrets stored in Azure Key Vault. Read Requirements for Secrets Rotation for more information.

     • AWS Secrets Manager: Provide the Amazon Resource Name (ARN) for the AWS Secrets Manager secret that holds the password, which is available in the AWS web console or using command line tools.

     • HashiCorp Vault: Choose the HashiCorp secrets engine you're using from the dropdown menu and enter the secret reference for the password in the correct format in the provided field.

   note

   Sources containing a large number of files or tables may take longer to be added. During this time, the source name is grayed out and shows a spinner icon, indicating the source is being added. Once complete, the source becomes accessible.

Advanced Options

Set the advanced configuration options for your database:

• Record fetch size: Number of records to fetch at once. Set to 0 to have Dremio automatically decide. By default, this is set to 10.
• Maximum idle connections: The total number of connections allowed to be idle at a given time. By default, this is set to 8.
• Connection idle time (s): The amount of time (in seconds) allowed for a connection to remain idle before the connection is terminated. By default, this is set to 60.
• Query timeout (s): The amount of time (in seconds) allowed to wait for the results of a query. If this time expires, the connection being used is returned to an idle state.
• Enable external authorization plugin: When enabled, authorizes an external plugin.
• Connection Properties: Connection properties and values for the data source.

Reflection Refresh

Set the policy that controls how often reflections are refreshed or expired, using the following options:

• Never refresh: Select to prevent automatic reflection refresh; otherwise, the default is to refresh automatically.
• Refresh every: How often to refresh reflections, specified in hours, days or weeks. This option is ignored if Never refresh is selected.
• Set refresh schedule: Specify the daily or weekly schedule.
• Never expire: Select to prevent reflections from expiring; otherwise, the default is to expire automatically after the time limit specified in Expire after.
• Expire after: The time limit after which reflections expire and are removed from Dremio, specified in hours, days or weeks. This option is ignored if Never expire is selected.

Metadata

Set the following metadata options:

• Remove dataset definitions if underlying data is unavailable: Checked by default. If this box is not checked and the underlying files under a folder are removed or the folder/source is not accessible, Dremio does not remove the dataset definitions. This option is useful in cases when files are temporarily deleted and put back in place with new sets of files.

• Data Discovery: Set the time interval for fetching top-level source object names such as databases and tables. You can choose to set the Fetch every frequency to fetch object names in minutes, hours, days, or weeks. The default frequency to fetch object names is 1 hour.

• Dataset Details: The metadata that Dremio needs for query planning such as information needed for fields, types, shards, statistics, and locality. Use these parameters to fetch or expire the metadata:

  • Fetch mode: Fetch only from queried datasets. Dremio updates details for previously queried objects in a source. By default, this is set to Only Queried Datasets.
  • Fetch every: Set the frequency to fetch dataset details in minutes, hours, days, or weeks. The default frequency to fetch dataset details is 1 hour.
  • Expire after: Set the expiry time of dataset details in minutes, hours, days, or weeks. The default expiry time of dataset details is 3 hours.

Privileges

To grant privileges to specific users or roles:

1. For Privileges, enter the user name or role name that you want to grant access to and click the Add to Privileges button. The added user or role is displayed in the USERS/ROLES table.
2. For the users or roles in the USERS/ROLES table, toggle the checkmark for each privilege you want to grant on the Dremio source that is being created.
3. Click Save after setting the configuration.

See Access Control for additional information about privileges.

Predicate Pushdowns

Dremio delegates the execution of these expressions and functions to the database being queried, often dramatically improving query performance. It can also offload entire SQL queries that include one or more of these expressions and functions.

*, +, -, /, %
<, <=, <>, =, >, >=, !=
AND, NOT, OR, ||
ABS
ACOS
ADD_MONTHS
ASIN
ATAN
ATAN2
AVG
CAST
CEIL
CEILING
CHAR_LENGTH
CHARACTER_LENGTH
CONCAT
COS
COT
DATE_ADD
DATE_SUB
DATE_TRUNC_DAY
DATE_TRUNC_HOUR
DATE_TRUNC_MINUTE
DATE_TRUNC_MONTH
DATE_TRUNC_YEAR
DEGREES
E
EXP
EXTRACT_DAY
EXTRACT_DOW
EXTRACT_DOY
EXTRACT_HOUR
EXTRACT_MINUTE
EXTRACT_MONTH
EXTRACT_QUARTER
EXTRACT_SECOND
EXTRACT_WEEK
EXTRACT_YEAR
FLOOR
IS DISTINCT FROM
IS NOT DISTINCT FROM
IS NOT NULL
IS NULL
LAST_DAY
LCASE
LEFT
LENGTH
LIKE
LN
LOCATE
LOG
LOG10
LOWER
LPAD
LTRIM
MAX
MEDIAN
MIN
MOD
MONTH
PERCENT_CONT
PERCENT_DISC
PI
POSITION
POW
POWER
RADIANS
RAND
REPLACE
REVERSE
RIGHT
ROUND
RPAD
RTRIM
SIGN
SIN
SQRT
SUBSTR
SUBSTRING
SUM
TAN
TIMESTAMPADD_DAY
TIMESTAMPADD_HOUR
TIMESTAMPADD_MINUTE
TIMESTAMPADD_MONTH
TIMESTAMPADD_QUARTER
TIMESTAMPADD_SECOND
TIMESTAMPADD_YEAR
TIMESTAMPDIFF_DAY
TIMESTAMPDIFF_HOUR
TIMESTAMPDIFF_MINUTE
TIMESTAMPDIFF_MONTH
TIMESTAMPDIFF_QUARTER
TIMESTAMPDIFF_SECOND
TIMESTAMPDIFF_WEEK
TIMESTAMPDIFF_YEAR
TO_DATE
TRIM
TRUNC
TRUNCATE
UCASE
UPPER
YEAR

Data Source Management

Updating the Source

To update the source:

1. On the Datasets page, under Databases in the panel on the left, find the name of the source you want to update.
2. Right-click the source name and select Settings from the dropdown.
3. In the Source Settings dialog, edit the settings you wish to update. Dremio does not support updating the source name.
4. Click Save.

Deleting the Source

If the source is in a bad state (for example, Dremio cannot authenticate to the source or the source is otherwise unavailable), only users who belong to the ADMIN role can delete the source.

To delete the source, perform these steps:

1. On the Datasets page, click Sources > Databases in the panel on the left.
2. In the list of data sources, hover over the name of the source you want to remove and click to the right.
3. From the dropdown, select Delete.
4. In the Delete Source dialog, click Delete to confirm that you want to remove the source.

note

• Deleting a source causes all downstream views that depend on objects in the source to break.
• Sources containing a large number of files or tables may take longer to be removed. During this time, the source name is grayed out and shows a spinner icon, indicating the source is being removed. Once complete, the source disappears.

Querying the Google BigQuery Source Directly

Dremio users can run pass queries through Dremio to run on your database. Doing so can sometimes decrease query execution times. For more information, see Querying Relational-Database Sources Directly.