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.
In the absence of entity integrity, the entries in a database can accidentally overlap, as there will be no way to pluck a specific entry from the table. When considering the first part of entity integrity, a unique value, the concept of a primary key is important to understand. A primary key in a database is a value used to specifically identify each individual record.