Constant INTERVAL_DAY_TIME_TYPE_REF

pub const INTERVAL_DAY_TIME_TYPE_REF: u32 = 2; // 2u32

For DataType::Interval with IntervalUnit::DayTime.

An i64 as:

• days: i32
• milliseconds: i32

See also ScalarValue::IntervalDayTime for the literal definition in DataFusion.