The materialized view %1 cannot be changed to immediate because it does not have a unique index on non-nullable columns

Error constant SQLE_IMMEDIATE_MV_NO_UNIQUE_INDEX
ODBC 2 state 42000
ODBC 3 state ERROR
Parameter 1 Name of the materialized view.
Severity 14
SQLCODE -1233
SQLSTATE 42WCA
Sybase error code 13284
 Probable cause
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