Time64

The Time64 data type allows storing time values with sub-second precision. Unlike DateTime64, it does not include a calendar date, but only represents time. The precision defines the resolution of stored values in fractional seconds.

Tick size (precision): 10^-precision seconds. Valid range: [ 0 : 9 ]. Typically, are used - 3 (milliseconds), 6 (microseconds), 9 (nanoseconds).

Syntax:

Time64(precision)

Internally, Time64 stores data as an Int64 number of ticks since the start of the day (000:00:00.000000000). The tick resolution is determined by the precision parameter. Optionally, a time zone can be specified at the column level, which affects how time values are interpreted and displayed in text format.

Unlike DateTime64, Time64 does not store a date component, meaning that it only represents time. See details in Time.

Supported range of values: [-999:59:59.999999999, 999:59:59.999999999]

The number of digits after the decimal point depends on the precision parameter.

Examples

Creating a table with Time64-type column and inserting data into it:

CREATE TABLE t64
(
    `timestamp` Time64(3),
    `event_id` UInt8
)
ENGINE = TinyLog;

-- Parse Time
-- - from integer interpreted as number of seconds since 1970-01-01.
-- - from string,
INSERT INTO t64 VALUES (15463123, 1), (154600.123, 2), ('100:00:00', 3);

SELECT * FROM t64;

   ┌─────timestamp─┬─event_id─┐
1. │  04:17:43.123 │        1 │
2. │  42:56:40.123 │        2 │
3. │ 100:00:00.000 │        3 │
   └───────────────┴──────────┘

Filtering on Time64 values

SELECT * FROM t64 WHERE timestamp = toTime64('100:00:00', 3);

   ┌─────timestamp─┬─event_id─┐
1. │ 100:00:00.000 │        3 │
   └───────────────┴──────────┘

Unlike Time, Time64 values are not converted from String automatically.

SELECT * FROM t64 WHERE timestamp = toTime64(154600.123, 3);

   ┌─────timestamp─┬─event_id─┐
1. │  42:56:40.123 │        2 │
   └───────────────┴──────────┘

Contrary to inserting, the toTime64 function will treat all values as the decimal variant, so precision needs to be given after the decimal point.

Getting a time zone for a Time64-type value:

SELECT toTime64(now(), 3) AS column, toTypeName(column) AS x;

   ┌────────column─┬─x─────────┐
1. │  19:14:16.000 │ Time64(3) │
   └───────────────┴───────────┘

See Also

Examples​

Examples