Greenville, South Carolina. For other uses, see Greenville. Greenville (/ËÉ¡riËnvÉªl/; locally /ËÉ¡riËnvÉl/) is the county seat of Greenville County in the upstate region of South Carolina, in the United States. The city's mayor is Knox White, who has served in that position since December 1995.
Non-key Attributes. back: surrogate key. next: derived attributes. Non-key attributes are attributes that are not part of a key. Generally, most attributes are simply descriptive, and fall into this category. Consider attributes for first name, last name, birth date; usually these attributes are non-key attributes.Consider a name attribute.on-key Attributes. back: surrogate key. next: derived attributes. Non-key attributes are attributes that are not part of a key. Generally, most attributes are simply descriptive, and fall into this category. Consider attributes for first name, last name, birth date; usually these attributes are non-key attributes.
Attributes can be classified as identifiers or descriptors. Identifiers, more commonly called keys or key attributes uniquely identify an instance of an entity. If such an attribute doesn't exist naturally, a new attribute is defined for that purpose, for example an ID number or code.uch an attribute is called a key attribute. For example, in the Employee entity type, EmpNo is the key attribute since no two employees can have same employee number. Similarly, for Product entity type, ProdId is the key attribute. There may be a case when one single attribute is not sufficient to identify entities.