Function timediff 

pub fn timediff<'a, V, E1, E2>(
    time1: E1,
    time2: E2,
) -> SQLExpr<'a, V, <V::DialectMarker as DialectTypes>::Text, <E1::Nullable as NullOr<E2::Nullable>>::Output, <E1::Aggregate as AggOr<E2::Aggregate>>::Output>
where
    V: SQLParam + 'a,
    V::DialectMarker: SQLiteDateTimeSupport,
    E1: Expr<'a, V>,
    E1::SQLType: Temporal,
    E2: Expr<'a, V>,
    E2::SQLType: Temporal,
    E1::Nullable: NullOr<E2::Nullable>,
    E2::Nullable: Nullability,
    E1::Aggregate: AggOr<E2::Aggregate>,

TIMEDIFF - computes the difference between two temporal values (SQLite 3.43+).

Returns a text representation of the time difference.

Example

use drizzle_core::expr::timediff;

// SELECT TIMEDIFF(events.end_time, events.start_time)
let duration = timediff(events.end_time, events.start_time);