I have a query that joins 2 tables, 1 table has 2 million records and other 1 million records, the query returns 1 record in less than 1 second, both the 2 tables being joined are accessed across a database link, despite the query running in less than a second, if I do a simple insert using the query it just hangs, and I don't understand why. The table is not locked, I have tried dropping the table before the insert and recreating it, to ensure there are no locks.
If I look at the wait events all I a can see this
I am running 12c on Windows, the database link is to database in another pluggable database in the same container.
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