title: PL/SQL iterate all schemas and run the same query on all of them
body: <p>I have various Oracle databases, eg ONE.db TWO.db THIRD.db etc and I want to run a SELECT which runs successfully on ONE.db, for example, <code>SELECT * FROM CUSTOMERS</code> etc. and then get the results per database. How can I do this using PL/SQL? (no db links or tools etc.)</p>