embedded-database

In Big Query there is a function array_concat_agg that aggregates array fields by concatenating the arrays. In Snowflake there is a flatten function that can unnest nested arrays into single array. I am looking for similar functionality in duckdb.

select flatten([[1, 2], [2, 3], [4, 5]] would return [1, 2, 2, 3, 4, 5]
I would also need a distinct option:
`select flatten(DISTINCT [[1, 2],

Right now, to get an acceptable experience in dtlv, one has to use rlwrap, i.e. launch it like this rlwrap dtlv. It would be nice to integrate with jline3 library to have a better experience natively.

> explain select 1
PhysicalProjection:
    1
  Dummy:

Currently, we are using Projection executor for select 1, which requires DummyExecutor to return one tuple. This is causing problems for many cases. For example,

> explain select count(*) from t1 where 0=1
PhysicalProjection:
    InputRef #0
  PhysicalSimpleAgg:
      count(InputRef #0) -> INT
    Dummy:
> sele