pub trait PgTimestampExpressionMethods: Expression + Sized {
// Provided method
fn at_time_zone<T>(self, timezone: T) -> AtTimeZone<Self, T>
where T: AsExpression<VarChar> { ... }
}
Available on crate feature
postgres_backend
only.Expand description
PostgreSQL specific methods present on timestamp expressions.
Provided Methods§
sourcefn at_time_zone<T>(self, timezone: T) -> AtTimeZone<Self, T>where
T: AsExpression<VarChar>,
fn at_time_zone<T>(self, timezone: T) -> AtTimeZone<Self, T>where T: AsExpression<VarChar>,
Creates a PostgreSQL “AT TIME ZONE” expression.
When this is called on a TIMESTAMP WITHOUT TIME ZONE
column,
the value will be treated as if were in the given time zone,
and then converted to UTC.
When this is called on a TIMESTAMP WITH TIME ZONE
column,
the value will be converted to the given time zone,
and then have its time zone information removed.
Example
let christmas_morning = NaiveDate::from_ymd(2017, 12, 25)
.and_hms(8, 0, 0);
diesel::insert_into(timestamps)
.values(timestamp.eq(christmas_morning))
.execute(connection)?;
let utc_time = timestamps
.select(timestamp.at_time_zone("UTC"))
.first(connection)?;
assert_eq!(christmas_morning, utc_time);
let eastern_time = timestamps
.select(timestamp.at_time_zone("EST"))
.first(connection)?;
let five_hours_later = christmas_morning + Duration::hours(5);
assert_eq!(five_hours_later, eastern_time);