WGU C170 Study Guide (Latest 2024/ 2025 Update) Data Management Applications Exam| 100% Correct| Grade A

WGU C170 Study Guide (Latest 2024/ 2025 Update) Data Management Applications Exam| 100% Correct| Grade A Q: domain: In data modeling, the construct used to organize and describe an attribute's set of possible values. Q: entity integrity Answer: The property of a relational table that guarantees each entity has a unique value in a primary key and that the key has no null values. Q: equijoin Answer: A join operator that links tables based on an equality condition that compares specified columns of the tables. Q: flags Answer: Special codes implemented by designers to trigger a required response, alert end users to specified conditions, or encode values. Q: foreign key (FK) Answer: An attribute or attributes in one table whose values must match the primary key in another table or whose values must be null. See key. Q: full functional dependence Answer: A condition in which an attribute is functionally dependent on a composite key but not on any subset of the key. Q: functional dependence Answer: An attribute B is functionally dependent on an attribute A if and only if a given value of attribute A determines exactly one value of attribute B. The relationship "B is dependent on A" is equivalent to "A determines B," and is written as A B. Q: homonyms Answer: The use of the same name to label different attributes. Q: index Answer: An ordered array of index key values and row ID values (pointers). Q: index key Answer: An ordered array of index key values. The same as index. Q: inner join Answer: A join operation in which only rows that meet a given criterion are selected. The join criterion can be an equality condition (natural join or equijoin) or an inequality condition (theta join). Q: INTERSECT Answer: In relational algebra, an operator used to yield only the rows that are common to two union-compatible tables. Q: JOIN Answer: In relational algebra, a type of operator used to yield rows from two tables based on criteria. There are many types of joins, such as natural join, theta join, equijoin, and outer join. Q: join columns Answer: Columns that are used in the criteria of join operations. The join columns generally share similar values (have a compatible domain). Q: key Answer: One or more attributes that determine other attributes. See also superkey, candidate key, primary key (PK), secondary key, and foreign key. Q: key attribute Answer: The attributes that form a primary key. See also prime attribute. Q: left outer join Answer: In a pair of tables to be joined, a join that yields all the rows in the left table, including those that have no matching values in the other table. Q: linking table Answer: In the relational model, a table that implements an M:M relationship. See also composite entity. Q: natural join A relational operation that yields a new table composed of only the rows with common values in their common attribute(s).