ORA-01502

ORA-01502: index 'string.string' or partition of such index is in unusable state

Cause: An attempt has been made to access an index or index partition that has been marked unusable by a direct load or by a DDL operation

Action: DROP the specified index, or REBUILD the specified index, or REBUILD the unusable index partition

Metalink:
Note:281500.1
-- initialization parameter SKIP_UNUSABLE_INDEXES in Oracle Database
-- Setting this parameter to TRUE disables error reporting of indexes and index partitions marked UNUSABLE.

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