Recommended Use of TIME Index Type

Use a TIME when the TIME column is used in queries containing time functions and operations.

Queries with DATEPART equality predicates (=, !=), DATEPART range predicates (>, <, >=, <=, !>, !<, BETWEEN) and DATEPART IN list predicates
Queries with range predicates (>, <, >=, <=, BETWEEN)

Note: For a simple equality predicate (no DATEPART) with a TIME column, LF and HG indexes have the best performance. If an LF or HG index is unavailable, theTIME index gets the result.

If a TIME or TIMESTAMP column is used in the GROUP BY clause or in the WHERE/HAVING clauses for equalities (including join conditions) or IN predicates, the column needs an LF or HG index, as only these indexes can do fast equality.