Yes, we've run into this one and various other data types like BLOB, CLOB, IMAGE, MEDIA, etc.. from various databases. We have often found that the actual data inside one of the fields is not supported by the source database and would also throw errors if you try to query it directly from a DB client.
Can you query this table/column/row using SQL Developer or SQL client? Does it return all results or fail? If you cannot query the data directly from a SQL client then you need to transform it or fix it in the source database. If you can query it from a DB client without errors, then I would start making sure that the Oracle version is fully supported.
Watch the Optim Temp logs to catch the Stored Procedure that it's failing on. The you can steal the Optim SP sql code to try and isolate where the failure is occurring.
That's my two cents. Tell us what you find if you solve it.
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Danny Lankford
3M - IT Manager
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