presto-hive/src/main/java/io/prestosql/plugin/hive/HiveSessionProperties.java/HiveSessionProperties/getInsertExistingPartitionsBehavior
class HiveSessionProperties:    public static InsertExistingPartitionsBehavior getInsertExistingPartitionsBehavior(ConnectorSession session)
    {
        return session.getProperty(INSERT_EXISTING_PARTITIONS_BEHAVIOR, InsertExistingPartitionsBehavior.class);
    }