Roadmap of Calcite support on Beam SQL?

[Jaehyeon Kim]

Hello,

I just tried a simple tumbling window but failed with the following error

RuntimeError: org.apache.beam.sdk.extensions.sql.impl.ParseException:
Unable to parse query
    WITH cte AS (
        SELECT TO_TIMESTAMP(event_datetime) AS ts FROM PCOLLECTION
    )
    SELECT
        CAST(window_start AS VARCHAR) AS start_time,
        CAST(window_end AS VARCHAR) AS end_time,
        COUNT(*) AS page_views
    FROM TABLE(
            TUMBLE(TABLE cte, DESCRIPTOR(ts), 'INTERVAL 1 MINUTE')
        )
    GROUP BY
        window_start, window_end

I guess it is because TO_TIMESTAMP is not implemented. When I check the
document, it misses lots of functions. Is there any roadmap about Calcite
support on Beam SQL?

Cheers,
Jaehyeon