I was thinking about adding [scrolling functionality](
to elastic search adapter. Since scrolling has non-negligible effect on the
cluster it should be selectively enabled on per query basis. So, likely,
user has to explicitly set "scroll flag" somewhere.
Most natural way seems in SQL. [Calcite sql grammar](
https://calcite.apache.org/docs/reference.html) has `SCROLL` keyword
(unused to my knowledge). There were also discussions about adding hints to
-- special sql keyword ?
SCROLL select * from elastic;
-- assuming hints are available in calcite
/* HINT: scroll */ select * from elastic;
What people think about this use-case ? Are there better ideas ?