presto-raptor-legacy/src/main/java/io/prestosql/plugin/raptor/legacy/metadata/DatabaseConfig.java/DatabaseConfig/setDatabaseType
class DatabaseConfig:    @Config("metadata.db.type")
    @ConfigDescription("Metadata database type (supported types: h2, mysql)")
    public DatabaseConfig setDatabaseType(String databaseType)
    {
        this.databaseType = databaseType;
        return this;
    }