@@ -37,7 +37,7 @@ With TDengine, the most important thing is timestamp. When creating and insertin
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@@ -37,7 +37,7 @@ With TDengine, the most important thing is timestamp. When creating and insertin
- Epch Time: a timestamp value can also be a long integer representing milliseconds since 1970-01-01 08:00:00.000.
- Epch Time: a timestamp value can also be a long integer representing milliseconds since 1970-01-01 08:00:00.000.
- Arithmetic operations can be applied to timestamp. For example: now-2h represents a timestamp which is 2 hours ago from the current server time. Units include u( microsecond), a (milliseconds), s (seconds), m (minutes), h (hours), d (days), w (weeks). In `select * from t1 where ts > now-2w and ts <= now-1w`, which queries data of the whole week before two weeks. To specify the interval of down sampling, you can also use n(calendar month) and y(calendar year) as time units.
- Arithmetic operations can be applied to timestamp. For example: now-2h represents a timestamp which is 2 hours ago from the current server time. Units include u( microsecond), a (milliseconds), s (seconds), m (minutes), h (hours), d (days), w (weeks). In `select * from t1 where ts > now-2w and ts <= now-1w`, which queries data of the whole week before two weeks. To specify the interval of down sampling, you can also use n(calendar month) and y(calendar year) as time units.
TDengiene's default timestamp is set to be accurate to a millisecond. Starting from `v2.1.5.0` precisions upto microseconds and nanoseconds are supported, this can be achieved by setting the PRECISION parameter passed during CREATE DATABASE.
TDengine's timestamp is set to millisecond resolution by default. Microsecond/nanosecond resolutions can be set using CREATE DATABASE with PRECISION parameter.(Nanosecond resolution is supported from version 2.1.5.0 onwards)
In TDengine, the following 10 data types can be used in data model of an ordinary table.
In TDengine, the following 10 data types can be used in data model of an ordinary table.
