Time Durations

GreptimeDB utilizes time durations to represent time spans in various contexts, including SQL queries, configuration files, and API requests. A time duration is expressed as a string composed of concatenated time spans, each represented by a sequence of decimal numbers followed by a unit suffix. These suffixes are case-insensitive and support both singular and plural forms. For example, 1hour 12min 5s.

Each time span consists of an integer and a suffix. The supported suffixes are:

• nsec, ns: nanoseconds
• usec, us: microseconds
• msec, ms: milliseconds
• seconds, second, sec, s
• minutes, minute, min, m
• hours, hour, hr, h
• days, day, d
• weeks, week, w
• months, month, M: defined as 30.44 days
• years, year, y: defined as 365.25 days

Appending a decimal integer with one of the above units represents the equivalent number of seconds as a bare float literal. Examples:

• 1s: Equivalent to 1 second
• 2m: Equivalent to 120 seconds
• 1ms: Equivalent to 0.001 seconds
• 2h: Equivalent to 7200 seconds

The following examples are invalid:

• 0xABm: Hexadecimal numbers are not supported
• 1.5h: Floating point numbers are not supported
• +Infd: ±Inf or NaN values are not supported

The following are some valid time duration examples:

• 1h: one hour
• 1h30m, 1h 30m: one hour and thirty minutes
• 1h30m10s, 1h 30m 10s: one hour, thirty minutes, and ten seconds