Generated keys are retrieved even if the primary key value is defined

[rtlusty]

Method DefaultDataAccessStrategy.insert(...) invokes method JdbcOperations.update(PreparedStatementCreator, KeyHolder) even in case, that the primary key is defined by the user. This creates probably some overhead and also fails on JDBC drivers, which don't support retrieving of generated keys.

The method should rather invoke JdbcOperations.update(PreparedStatementCreator) in case, that the primary key value is already defined in time of INSERT.

[schauder]

Related Stackoverflow question: https://stackoverflow.com/q/66459999/66686

@rtlusty Are you interested in providing a PR for this?

[rtlusty]

@schauder Sure, I will try.