Delay on next connection when user select "Only show users that own objects" (4276234)

After selecting View | Option | Schema Browser | Data | "Only show users that show own objects", connection to a v10.2.0.1.0 database, takes a long time.

The Explain Plan on this query is very large - full of full table scans of x$ tables and nested loops, both of which lead to the delay.

WORKAROUND 1:
Change the View | Option | Schema Browser | Data to All Users, then reconnect to the database using Toad.

WORKAROUND 2:
If working with 10g, gather statistics on the data dictionary.

WORKAROUND 3:
If using a setting other then   "Show all users", set hidden Oracle parameter "_optimizer_cost_based_transformation" OFF.

CREATE OR REPLACE TRIGGER logon_trigger
  after logon on USER.schema
begin
  execute immediate 'alter session set
"_optimizer_cost_based_transformation"=off';
end;

Refer to Note 313746.1 on MetaLink :
          Problem - "Oracle 10G query is slow compared to Oracle 9i.,"
          Solution - Alter session set "_optimizer_cost_based_transformation" = OFF;

STATUS:

An enhancement request has been submitted to Development for consideration in future release of TOAD.