to all non-primary key (nonpk) fields of the Survey entity and these attributes are optional. As output, the service returns attributes corresponding to the primary key (pk) fields of Survey, i.e., in this case the surveyId field, and these attributes are mandatory. The purpose of the reference across languages is in this case to reduce redundancy. The attributes of the createSurvey service corresponds to the fields of the Survey entity and it is therefore only necessary to specify them once.

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