C170 Data Management WITH 100% CORRECT ANSWER
The order of the rows and columns is important to the DBMS. True or False False PRODUCT yields all possible pairs of rows from two tables, also known as the _______ product. Cartesian According to Codd's ______ rule of relation database, "Application programs and ad hoc facilities are logically unaffected when changes are made to the table structures that preserve the original table values (changing order of columns or inserting columns)." A. comprehensive data sublanguage B. integrity independence C. D. The ______ relationship is the relation database norm. 1:M (1 to many) A table is also called a relation because the relation model's creator, E.F. Codd used the two terms as: A. Synonyms B. Homonyms C. Entities D. Attributes A. Synonyms The relational operators have the property of ________ ; that is, the use of relational algebra operators on existing relations (tables) produces new relations. Closure A _________ join links tables by selecting only the rows with common values in their common attribute(s). A. Attribute B. Unique C. Foreign D. Natural D. Natural A _______ key can be described as a minimal superkey, a superkey without any unnecessary attributes. A. Candidate B. Secondary C. Foreign D. Primary A. Candidate True or False: Character data type is also known as string data type, can contain any character or symbol not intended for mathematical manipulation, but character sets can include digits or a numeric string. True A ______ is the primary key of one table that has been placed into another table to create a common attribute. A. superkey B. composite primary key C. candidate key D. foreign key D. foreign key In a relational model, ________ are also used to establish relationships among tables and to ensure the integrity of the data. Keys Rows are sometimes referred to as ________. A. Records B. Files C. Fields A. Records True or False In a natural join, the column on which the join was made occurs twice in the new table. False When two or more tables share the same number of columns, and when their corresponding columns share the same or compatible domains, they are said to be _______. A. select-compatible B. intersect-compatible C. union-compatible D. difference-compatible C. union-compatible _____ logic, used extensively in mathematics, provides a framework in which an assertion (or statement of fact) can be verified as either true or false. A. Index B. Relational C. Database D. Predicate D. Predicate _______ is the real power behind the relational database, allowing the use of independent tables linked by common attributes Join A(n) ___________ only returns matched records from the tables that are being joined. A. equijoin B. inner join C. outer join D. theta join B. Inner join If one department char "a professor" can chair only one department and one department can only have one department chair, the entities PROFESSOR and DEPARTMENT exhibit a __________ relationship 1:1 (1 to 1) True or False A candidate key is a minimal superkey without any unnecessary attributes True The proper use of __________ keys is crucial to controlling data redundancy. Foreign The CUSTOMER table's primary key is CUS_CODE. The CUSTOMER primary key column has no null entries, and all entries are unique. This is an example of _____ integrity. A. Referential B. Relational C. Null D. Entity D. Entity
Información del documento
- Subido en
- 3 de septiembre de 2023
- Número de páginas
- 46
- Escrito en
- 2023/2024
- Tipo
- Examen
- Contiene
- Preguntas y respuestas