In OceanBase MySQL mode, the NOW() and CURRENT_TIMESTAMP functions return time with microsecond precision (up to 6 decimal places).

If your OceanBase instance is running in Oracle mode, functions like SYSTIMESTAMP and CURRENT_TIMESTAMP can return time with nanosecond precision (up to 9 decimal places).

If you need nanosecond-level timestamps in MySQL mode, you can generate them using external applications — for example, with System.nanoTime() in Java or time.Now().UnixNano() in Go — and store them in the database as BIGINT or a custom-formatted string.