Oracle allows indexes to be created using a function rather than a column. Example:

CREATE INDEX OPS_OPERATED_SECTOR_N10
ON OPS_OPERATED_SECTOR (TRUNC(DEPARTURE_DATETIME) ASC)

This causes an exception:
org.hibernate.tool.schema.spi.SchemaManagementException: Could not locate column information using identifier [SYS_NC00137$]
at org.hibernate.tool.schema.extract.internal.InformationExtractorJdbcDatabaseMetaDataImpl.getIndexes(InformationExtractorJdbcDatabaseMetaDataImpl.java:550)