Study Guide 2024)

Optional Relationship participation {Ans: one entity occurrence does not require a corresponding entity occurrence in a particular relationship}single-value attribute {Ans: holds a single value for each occurrence of an entity type}data dependence {Ans: A data condition in which data representation and manipulation are dependent on the physical data storage characteristics.}examples of data redundancy {Ans: Inconsistency in data format The same information being kept in several different places (files) Data inconsistency, a situation where various copies of the same data are conflicting, wastes storagespace and duplicates effort}relation {Ans: another term for table}Homogeneous distributed database systems {Ans: use the same DBMS software at multiple sites}Properties of a Table {Ans: A table has a name that is distinct from all other tables in the database. • There are no duplicate rows; each row is distinct. • Entries in columns are atomic. The table does not contain repeating groups or multivalued attributes. • Entries from columns are from the same domain based on their data type including:number (numeric, integer, float, smallint,...)character (string)datelogical (true or false) • Operations combining different data types are disallowed. • Each attribute has a distinct name. • The sequence of columns is insignificant.