Insert statement to table from view is taking too long sometimes.

Hi Everyone,

We have a daily script that runs an insert statement into a table from a view. This insert sometimes gets stuck for more than 7hrs, while sometimes it completes within 2 (which is expected timeframe). Is there any particular reason this can happen? The target table lies in a different Tablespace than the tables that the view accesses. Please help. Is there any known cause to this?

Thanks,

Debo