Cause
User attempted to add or enable a primary key/unique constraint on column(s) of a table on which there exists an index one or more partitions of which are marked Index Unusable.
User attempted to add or enable a primary key/unique constraint on column(s) of a table on which there exists an index one or more partitions of which are marked Index Unusable.
Avoid modifying data type and/or length of index partitioning column(s)
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
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