Trying to compare same schemas in two 12.2.0.2 databases for constraints, my toad for Oracle 12.8.0.49 generated an error: list index out of bounds (0)

clarity schemas fo eddwprd and edwdev. Compare only constraints (no check constraint, but including FK, unique index and primary key)

generated error is: list of index out of bounds(0).

When I compare schemas of entire schema objects, it went farther, eventually generated more than 1000 differences and failed.

I used utility\copy user setting to reset customerized config (I did not have any because this is a new laptop and a new install), but that did not help with the error.

I need to compare different object types of the schema to sync the newly refreshed clarity schema in the second database.

Please help.

Thanks.

Yinhai