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

Error constant SQLE_UPDATABLE_MATVIEW_NON_AGGR_INDEX
ODBC 2 state 42000
ODBC 3 state ERROR
Severity 16
SQLCODE -1218
SQLSTATE 42WC7
Sybase error code 13299
 Probable cause
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