If you make use of a "timestamp" datatype in your mapping of java code (java.util.Date) and have a roundtrip through the entity mapping of hibernate to the database you might loose resolution. While in SQLServer2008Dialect "timestamp" is mapped to the mssql datatype datetime2 which defaults to datetime2(7) in the HSQLDialect you find a mapping to the hsql datatype timestamp which defaults to timestamp(6). https://docs.microsoft.com/de-de/sql/t-sql/data-types/datetime2-transact-sql?view=sql-server-ver15 http://hsqldb.org/doc/2.0/guide/sqlgeneral-chapt.html#sgc_datetime_types |