create table batch (
    entity text,
    start_ts timestamptz,
    duration interval
)
;

create table active_events (
    entity text,
    start_ts timestamptz,
    end_ts timestamptz
)
;

create table active_events as
with
    new_events as materialized (  -- Does not make much sense in this example, but my original query was a union of a bunch of things
        select
            entity,
            start_ts as start_ts,
            start_ts + duration as end_ts
        from
            batch
    ), events_to_deduplicate as (
        select
            *
        from  -- We need to deduplicate events for old entites with new data
            active_events old
            semi join new_events new on
                old.entity = new.entity
        union all
        select *
        from
            new_events
    ), combined_deduplicated_events as (
        select
            entity,
            min(start_ts) as start_ts,
            max(end_ts) as end_ts
        from
            events_to_deduplicate
        group by
            entity
    ), all_events as (
        select
            entity,
            start_ts,
            end_ts
        from
            combined_deduplicated_events
        where
            end_ts > start_ts
        union all
        select
            *
        from  -- The data we did not need to deduplicate
            active_events old
            anti join new_events new on
                old.entity = new.entity
    )
select
    *
from
    combined_leases
;