EclipseLink nullable column but unique -

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is possible define column eclipselink, can null if value != null exists, there should unique values within column. how can model that?

thank you

andre

what type of value?

i enforce uniqueness in object model, not in database. if want restrict in database, add check constraint in own ddl script.

in java can use enum or type code or value , restrict through set methods.

eclipselink have @objecttypeconverter allows conversion between set of values.


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