To use this Apache Druid extension, [include](../../development/extensions.md#loading-extensions) `mysql-metadata-storage` in the extensions load list.
## Alternative: Installing the MariaDB connector library
This extension also supports using the MariaDB connector jar, though it is also not included in the Druid distribution, so you must install it separately.
- Download from the MariaDB site: https://mariadb.com/downloads/connector
- Download from Maven Central: https://repo1.maven.org/maven2/org/mariadb/jdbc/mariadb-java-client/2.7.3/mariadb-java-client-2.7.3.jar
This fetches the MariaDB connector JAR file with a name like `maria-java-client-2.7.3.jar`.
Copy or symlink this file to `extensions/mysql-metadata-storage` under the distribution root directory.
To configure the `mysql-metadata-storage` extension to use the MariaDB connector library instead of MySQL, set `druid.metadata.mysql.driver.driverClassName=org.mariadb.jdbc.Driver`.
Depending on the MariaDB client library version, the connector supports both `jdbc:mysql:` and `jdbc:mariadb:` connection URIs. However, the parameters to configure the connection vary between implementations, so be sure to [check the documentation](https://mariadb.com/kb/en/about-mariadb-connector-j/#connection-strings) for details.
This extension also supports using MariaDB server, https://mariadb.org/download/, substituting for MariaDB in the following instructions where appropriate.
This extension provides support for encrypting MySQL connections. To get more information about encrypting MySQL connections using TLS/SSL in general, please refer to this [guide](https://dev.mysql.com/doc/refman/5.7/en/using-encrypted-connections.html).
|`druid.metadata.mysql.ssl.clientCertificateKeyStorePassword`|The [Password Provider](../../operations/password-provider.md) or String password for the client key store.|none|no|
|`druid.metadata.mysql.ssl.verifyServerCertificate`|Enables server certificate verification.|false|no|
|`druid.metadata.mysql.ssl.trustCertificateKeyStoreUrl`|The file path to the trusted root certificate key store.|Default trust store provided by MySQL|yes if `verifyServerCertificate` is set to true and a custom trust store is used|
|`druid.metadata.mysql.ssl.trustCertificateKeyStoreType`|The type of the key store where trusted root certificates are stored.|JKS|yes if `verifyServerCertificate` is set to true and keystore type is not JKS|
|`druid.metadata.mysql.ssl.trustCertificateKeyStorePassword`|The [Password Provider](../../operations/password-provider.md) or String password for the trust store.|none|yes if `verifyServerCertificate` is set to true and password is not null|