UTC TIMESTAMP indicates the Coordinated Universal (UTC) time when each row in the table was last modified.
When a column is declared with DEFAULT UTC TIMESTAMP, a default value is provided for inserts, and the value is updated with the current UTC date and time 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 current 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.
The main difference between DEFAULT UTC TIMESTAMP and DEFAULT CURRENT UTC TIMESTAMP is that DEFAULT CURRENT UTC TIMESTAMP is set only at INSERT, while DEFAULT UTC TIMESTAMP is set at both INSERT and UPDATE.