that was my point.
I thought you said you said sourceid exists on SQL Server., and assumed you were doing the work from SQL server, with linked servers to Oracle.
What confused me was test@dblink_test I think you are saying that is a dblink TO SQL Server?
so your commands are all originating on the Oracle side, not SQL Server, correct?
What Table does source_id exist in?
i would be lazy, and on SQL Server,create a view that formats the the source_id to CONVERT(VARCHAR(35),source_id,121)
this is actually an Oracle question, and dblink behavior, and not really a SQL question, which is causing all the confusion...you ar egetting SQL-oriented answers from us.
see this post, where they specifically say you need to cast it to a char to get timestamps:
https://forums.oracle.com/forums/thread.jspa?threadID=2359176
Lowell