The DB Adapter has some nice features, but sometimes you can get fooled. One of my colleagues experiences this one day. The query returned the same row - just repeated many times.
The reason for this is because the primary key was not defined correctly.
The good thing is that the documentation describes this - and more: Oracle documentation
For tables where primary key is defined - this should not be a problem, but in cases where it is not defined or you are querying a view - you would need to specify a primary key yourself. A couple of relevant notes here:
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