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This error is occurs because the statistics belonging to the External Table cannot be collected while collecting the statistics belonging to the tables.
Solution:
We drop the External Tables.
We find the External Tables in the database as follows.
The directories belonging to the SYS user are listed from TOAD. There, the external table tab belonging to each directory is clicked and the tables are found.
1 2 3 4 5 6 7 | SQL> DROP TABLE EXTERNAL_ACCOUNT; Table dropped. SQL> DROP TABLE EXTERNAL_TEST_ABONE; Table dropped. |
