UTC TIMESTAMP special value

The UTC TIMESTAMP default value is used to record the Coordinated Universal Time (UTC) when a row in a table was last modified.

Remarks

The fraction of a second is stored to 6 decimal places. The accuracy of the present time is limited by the accuracy of the system clock.

When a column is declared with DEFAULT UTC TIMESTAMP, a default value is provided for inserts, and the value is updated with the present UTC date and time of day whenever the row is updated.

Columns declared with DEFAULT UTC TIMESTAMP contain unique values so that applications can detect near-simultaneous updates to the same row. If the present UTC timestamp value is the same as the last value, it is incremented by the value of the default_timestamp_increment option.

You can automatically truncate UTC TIMESTAMP values in SQL Anywhere with the default_timestamp_increment option. This is useful for maintaining compatibility with other database software that records less precise timestamp values.

Note

DEFAULT UTC TIMESTAMP is set at both INSERT and UPDATE and DEFAULT CURRENT UTC TIMESTAMP is set at INSERT.

Standards and compatibility

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