Yes, only I think having a uni-directional dataset is going to limit it's usefulness. I have now got my TOracleDataset reading all fields except the BLOB, and a TQuery querying to retrieve the BLOB separately on the dataset's OnDataChange event, and it all works very nicely. I was very impressed with how easy it was to export my BLOB into a TBitmap. Freeing the TLOBLocator each time stops my memory problem.

Thanks!