session references process private memory; cannot detach session

session references process private memory; cannot detach session

This error is comming as usual to oracle DBA in everytime

Here is the cause and ways to avoid this error


Reason

An attempt was made to detach the current session when it contains
references to process private memory.


Action

A session may contain references to process memory (PGA) if it has
an open network connection, a very large context area, or operating
system privileges. To allow the detach, it may be necessary to
close the session's database links and/or cursors. Detaching a
session with operating system privileges is always disallowed.