Function truncate_date

src/functions/datetime_functions.rs:434–523

Truncate microseconds since epoch to the specified precision

(field: &str, timestamp: i64)

/// Truncate microseconds since epoch to the specified precision
fn truncate_date(field: &str, timestamp: i64) -> Result<i64> {
    let secs = timestamp / 1_000_000;
    let micros = timestamp % 1_000_000;
    let nanos = (micros * 1000) as u32;
    
    let datetime = DateTime::from_timestamp(secs, nanos)
        .ok_or_else(|| Error::UserFunctionError("Invalid timestamp".into()))?;
    
    let truncated = match field.to_lowercase().as_str() {
        "microseconds" => {
            // Already at microsecond precision
            timestamp
        }
        "milliseconds" => {
            // Truncate to millisecond
            (timestamp / 1000) * 1000
        }
        "second" => (timestamp / 1_000_000) * 1_000_000,
        "minute" => {
            let dt = datetime.date_naive().and_hms_opt(datetime.hour(), datetime.minute(), 0).unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "hour" => {
            let dt = datetime.date_naive().and_hms_opt(datetime.hour(), 0, 0).unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "day" => {
            let dt = datetime.date_naive().and_hms_opt(0, 0, 0).unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "week" => {
            // Truncate to start of week (Monday)
            let days_from_monday = datetime.weekday().num_days_from_monday();
            let start_of_week = datetime.date_naive() - chrono::Duration::days(days_from_monday as i64);
            let dt = start_of_week.and_hms_opt(0, 0, 0).unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "month" => {
            let dt = NaiveDate::from_ymd_opt(datetime.year(), datetime.month(), 1)
                .unwrap()
                .and_hms_opt(0, 0, 0)
                .unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "quarter" => {
            let quarter_month = ((datetime.month() - 1) / 3) * 3 + 1;
            let dt = NaiveDate::from_ymd_opt(datetime.year(), quarter_month, 1)
                .unwrap()
                .and_hms_opt(0, 0, 0)
                .unwrap();
            dt.and_utc().timestamp() * 1_000_000
        }
        "year" => {
            let dt = NaiveDate::from_ymd_opt(datetime.year(), 1, 1)
                .unwrap()
                .and_hms_opt(0, 0, 0)
                .unwrap();
            dt.and_utc().timestamp() * 1_000_000