(Required) Specifies the Table, JoinTable, SecondaryTable or TableGenerator attribute which this UniqueConstraint attribute belongs to. This Unique constraint represents a Unique constraint that is to be placed on the table. it is only used if table generation is in effect. the constraint applys in addition to any constraints specified by the Column and JoinColumn annotations and constraints entailed by primary key mappings. Defaults to no additional constraints

public string TableRef