MySQL, MariaDB, and SingleStore

Dialects that use these instructions

MySQL, MariaDB, and SingleStore (formerly MemSQL) share the database setup requirements described on this page.

Encrypting network traffic

It is a best practice to encrypt network traffic between the Looker application and your database. Consider one of the options described on the Enabling secure database access documentation page.

If you're interested in using SSL encryption, see this MySQL documentation page.

Users and security

To create and grant the required access to the Looker user, follow the instructions in the section appropriate to your database dialect and version:

MySQL 8.0.X:

Note: The Looker MySQL 8.0.X dialect option is implemented with the patch version 8.0.12+ because of a MySQL deprecation in implicit sorting in the GROUP BY clause. This affects Looker subtotals for MySQL versions 8.0.0 through 8.0.11, causing SQL generation errors. Looker suggests upgrading any MySQL 8.0.X databases to at least 8.0.12 to fully integrate. However, earlier MySQL versions will still work, aside from subtotals.

In MySQL 8.0.X, the default authentication plugin is caching_sha2_password. Looker uses the mysql_native_password plugin to attempt to authenticate to MySQL databases through the JDBC driver. For this version of MySQL to work properly, you must take the following additional steps:

1. Configure the MySQL database to use the mysql_native_password plugin. This can be done in multiple ways, and will depend on how your MySQL 8 database is deployed and what type of access you have to the configuration:

   • Start the process with the flag --default-auth=mysql_native_password

   • Set the property in the my.cnf configuration file:

   [mysqld]
   default-authentication-plugin=mysql_native_password
   

   • If your database instance is hosted through AWS RDS, set the default_authentication_plugin parameter through an RDS Parameter Group that is applied to this database instance.

2. Run the following commands, replacing some_password_here with a unique, secure password:

   CREATE USER looker IDENTIFIED WITH mysql_native_password BY 'some_password_here';
   GRANT SELECT ON database_name.* TO 'looker'@'%';
   

MySQL 5.7.X and earlier, MariaDB, and SingleStore:

Run the following commands, replacing some_password_here with a unique, secure password:

CREATE USER looker;
SET PASSWORD FOR looker = PASSWORD ('some_password_here');
GRANT SELECT ON database_name.* TO 'looker'@'%';

Temp schema setup for persistent derived tables

These database dialects support the creation of persistent derived tables (PDTs). This feature can be very useful, and we recommend enabling it when possible.

To enable PDTs, you need to configure a temp schema. The following commands show an example of creating a temp database and granting the required privileges to the looker user.

You can specify the name of the temp database in the Temp Database field when creating your database connection. If you don't specify a temp database name, Looker generates a scratch database named looker_tmp. The following commands use looker_tmp, but if you specified a different temp database name, use your temp database name instead of looker_tmp.

CREATE SCHEMA looker_tmp;
GRANT
  SELECT,
  INDEX,
  INSERT,
  UPDATE,
  DELETE,
  CREATE,
  DROP,
  ALTER,
  CREATE TEMPORARY TABLES
ON looker_tmp.* TO 'looker'@'%';

For SingleStore, or if your database uses GTID-based replication, you must use the create_process LookML parameter to use PDTs, because GTID does not support CREATE TABLE AS SELECT statements.

Alternative setup for regular derived tables

If you do not want to allow the creation of persistent derived tables, you can still use regular derived tables. To use regular derived tables, you still need to add certain permissions to a schema called looker_tmp. However, the looker_tmp schema does not actually need to exist in your database!

GRANT
  SELECT,
  INDEX,
  INSERT,
  DROP,
  CREATE TEMPORARY TABLES
ON looker_tmp.* TO 'looker'@'%';
-- Note that the looker_tmp schema does not need to actually exist,
-- even though these permission grants are still needed

Setting the max_allowed_packet variable

For MySQL, set the MySQL max_allowed_packet variable to its maximum value, 1073741824, to prevent "SQLException: Packet for query is too large" errors.

Creating the Looker connection to your database

After completing the database configuration, you can connect to the database from Looker. Follow these steps to create the connection from Looker to your database:

1. In the Admin section of Looker, select Connections, and then click Add Connection.

2. From the Dialect drop-down menu, select your database dialect name: MySQL, MySQL 8.0.12+, MariaDB, SingleStore, or SingleStore 7+.

   Note: If you are on a Looker (Google Cloud core) instance and you don't see your dialect listed in the Dialect drop-down menu, see the Looker (Google Cloud core) documentation to verify that the dialect is supported for Looker (Google Cloud core) instances.

3. Fill out the connection details. The majority of the settings are common to most database dialects. See the Connecting Looker to your database documentation page for information.

4. To verify that the connection is successful, click Test. See the Testing database connectivity documentation page for troubleshooting information.

5. To save these settings, click Connect.

Feature support

For Looker to support some features, your database dialect must also support them.

MySQL supports the following features as of Looker 24.14:

Feature	Supported?
Support Level	Supported
Looker (Google Cloud core)	No
Symmetric Aggregates	Yes
Derived Tables	Yes
Persistent SQL Derived Tables	Yes
Persistent Native Derived Tables	Yes
Stable Views	Yes
Query Killing	Yes
SQL-based Pivots	Yes
Timezones	Yes
SSL	Yes
Subtotals	Yes
JDBC Additional Params	Yes
Case Sensitive	No
Location Type	Yes
List Type	Yes
Percentile	Yes
Distinct Percentile	Yes
SQL Runner Show Processes	Yes
SQL Runner Describe Table	Yes
SQL Runner Show Indexes	Yes
SQL Runner Select 10	Yes
SQL Runner Count	Yes
SQL Explain	Yes
Oauth Credentials	No
Context Comments	Yes
Connection Pooling	No
HLL Sketches	No
Aggregate Awareness	Yes
Incremental PDTs	Yes
Milliseconds	Yes
Microseconds	Yes
Materialized Views	No
Approximate Count Distinct	No

MySQL 8.0.12+ supports the following features as of Looker 24.14:

Feature	Supported?
Support Level	Supported
Looker (Google Cloud core)	Yes
Symmetric Aggregates	Yes
Derived Tables	Yes
Persistent SQL Derived Tables	Yes
Persistent Native Derived Tables	Yes
Stable Views	Yes
Query Killing	Yes
SQL-based Pivots	Yes
Timezones	Yes
SSL	Yes
Subtotals	Yes
JDBC Additional Params	Yes
Case Sensitive	No
Location Type	Yes
List Type	Yes
Percentile	Yes
Distinct Percentile	Yes
SQL Runner Show Processes	Yes
SQL Runner Describe Table	Yes
SQL Runner Show Indexes	Yes
SQL Runner Select 10	Yes
SQL Runner Count	Yes
SQL Explain	Yes
Oauth Credentials	No
Context Comments	Yes
Connection Pooling	No
HLL Sketches	No
Aggregate Awareness	Yes
Incremental PDTs	Yes
Milliseconds	Yes
Microseconds	Yes
Materialized Views	No
Approximate Count Distinct	No

MariaDB supports the following features as of Looker 24.14:

Feature	Supported?
Support Level	Supported
Looker (Google Cloud core)	Yes
Symmetric Aggregates	Yes
Derived Tables	Yes
Persistent SQL Derived Tables	Yes
Persistent Native Derived Tables	Yes
Stable Views	Yes
Query Killing	Yes
SQL-based Pivots	No
Timezones	Yes
SSL	Yes
Subtotals	Yes
JDBC Additional Params	Yes
Case Sensitive	No
Location Type	Yes
List Type	Yes
Percentile	Yes
Distinct Percentile	Yes
SQL Runner Show Processes	Yes
SQL Runner Describe Table	Yes
SQL Runner Show Indexes	Yes
SQL Runner Select 10	Yes
SQL Runner Count	Yes
SQL Explain	Yes
Oauth Credentials	No
Context Comments	Yes
Connection Pooling	No
HLL Sketches	No
Aggregate Awareness	Yes
Incremental PDTs	No
Milliseconds	Yes
Microseconds	Yes
Materialized Views	No
Approximate Count Distinct	No

SingleStore supports the following features as of Looker 24.14:

Feature	Supported?
Support Level	Supported
Looker (Google Cloud core)	No
Symmetric Aggregates	Yes
Derived Tables	Yes
Persistent SQL Derived Tables	Yes
Persistent Native Derived Tables	Yes
Stable Views	Yes
Query Killing	Yes
SQL-based Pivots	Yes
Timezones	Yes
SSL	Yes
Subtotals	Yes
JDBC Additional Params	Yes
Case Sensitive	No
Location Type	Yes
List Type	Yes
Percentile	No
Distinct Percentile	No
SQL Runner Show Processes	Yes
SQL Runner Describe Table	Yes
SQL Runner Show Indexes	Yes
SQL Runner Select 10	Yes
SQL Runner Count	Yes
SQL Explain	Yes
Oauth Credentials	No
Context Comments	Yes
Connection Pooling	No
HLL Sketches	No
Aggregate Awareness	Yes
Incremental PDTs	No
Milliseconds	Yes
Microseconds	Yes
Materialized Views	No
Approximate Count Distinct	No

SingleStore 7+ supports the following features as of Looker 24.14:

Feature	Supported?
Support Level	Supported
Looker (Google Cloud core)	Yes
Symmetric Aggregates	Yes
Derived Tables	Yes
Persistent SQL Derived Tables	Yes
Persistent Native Derived Tables	Yes
Stable Views	Yes
Query Killing	Yes
SQL-based Pivots	Yes
Timezones	Yes
SSL	Yes
Subtotals	Yes
JDBC Additional Params	Yes
Case Sensitive	No
Location Type	Yes
List Type	Yes
Percentile	Yes
Distinct Percentile	No
SQL Runner Show Processes	Yes
SQL Runner Describe Table	Yes
SQL Runner Show Indexes	Yes
SQL Runner Select 10	Yes
SQL Runner Count	Yes
SQL Explain	Yes
Oauth Credentials	No
Context Comments	Yes
Connection Pooling	No
HLL Sketches	No
Aggregate Awareness	Yes
Incremental PDTs	No
Milliseconds	Yes
Microseconds	Yes
Materialized Views	No
Approximate Count Distinct	No