Whether the sort direction is descending (true) or ascending (false).
Whether ASC was explicitly written (not just implied)
Some(true) = NULLS FIRST, Some(false) = NULLS LAST, None = unspecified.
The expression to sort by.
Optionalwith_ClickHouse WITH FILL clause
Represent an expression with sort direction and null ordering.
Used inside ORDER BY clauses, window frame ORDER BY, and index definitions. When
descis false the sort is ascending. Thenulls_firstfield controls the NULLS FIRST / NULLS LAST modifier;Nonemeans unspecified (database default).