Problems with RANK()

Looks like I'm running into a problem with RANK(). The following works:

SELECT r2_1.store__id, r2_1.month_of_year__id,
    r2_1.fact_sales_sales_amt AS "amount",
    RANK() OVER (PARTITION BY r2_1.store__id ORDER BY r2_1.fact_sales_sales_amt) AS "__window_pred1"
FROM
(
    -- leaf_node(a, fact_sales)
    SELECT fact_sales.store_id AS store__id, max_dim_date.the_month AS month_of_year__id,
        SUM(fact_sales.sales_amt) AS fact_sales_sales_amt, SUM(fact_sales.tax_amt) AS fact_sales_tax_amt
    FROM fact_sales
    JOIN max_dim_date
      ON max_dim_date.the_date = fact_sales.the_date
    GROUP BY fact_sales.store_id, max_dim_date.the_month
) AS r2_1

But the following gives me an error: TIOStreamTransport.java:read:130:org.apache.thrift.transport.TTransportException: Socket is closed by peer.

SELECT r2_1.store__id, r2_1.month_of_year__id,
    r2_1.fact_sales_sales_amt AS "amount",
    RANK() OVER (PARTITION BY r2_1.store__id ORDER BY r2_1.fact_sales_sales_amt) AS "__window_pred1"
FROM
(
    -- leaf_node(a, fact_sales)
    SELECT fact_sales.store_id AS store__id, max_dim_date.the_month AS month_of_year__id,
        SUM(fact_sales.sales_amt) AS fact_sales_sales_amt, SUM(fact_sales.tax_amt) AS fact_sales_tax_amt
    FROM fact_sales
    JOIN max_dim_date
      ON max_dim_date.the_date = fact_sales.the_date
    GROUP BY fact_sales.store_id, max_dim_date.the_month
) AS r2_1

I consistently lose my connection (using DBeaver) when I run this query. Is there a way to find out more details about the Omnisci error? I'm guessing that RANK() has problems when I introduce that second node that I join to.