Well, again, that is not completely straightforward - what exactly is a "persisted object"? We have two things here that are usually called entities:
1. The domain entities, which are normally represented as native objects in our codebase. They have no idea whether they need to be persisted and how.
2. The database entities, which are - in RDBs at least - represented by tables.
It is not uncommon that our entities of the first type can easily be mapped 1:1 to our entities of the second type - but that is far from guaranteed. Even if this is the case, the entities will be different because of the differences between the two "worlds": for example, Python's integer type doesn't have a direct equivalent in, say, PostgreSQL (it has to be converted into smallint, integer, bigint or numeric).
In my "correction" above I was talking about the domain entities, and my phrasing that they "need database access" is not fully correct; it should have been "need to be persisted", to be pedantic.
1. The domain entities, which are normally represented as native objects in our codebase. They have no idea whether they need to be persisted and how.
2. The database entities, which are - in RDBs at least - represented by tables.
It is not uncommon that our entities of the first type can easily be mapped 1:1 to our entities of the second type - but that is far from guaranteed. Even if this is the case, the entities will be different because of the differences between the two "worlds": for example, Python's integer type doesn't have a direct equivalent in, say, PostgreSQL (it has to be converted into smallint, integer, bigint or numeric).
In my "correction" above I was talking about the domain entities, and my phrasing that they "need database access" is not fully correct; it should have been "need to be persisted", to be pedantic.