Which of the following statement is true? A primary key is a minimal candidate key A...
Which of the following statement is true?
A primary key is a minimal candidate key
A candidate key is a a set of attributes for which, if we remove any attribute, it will lose the key property If we add an extra attribute to a super key, it will become a candidate key
A super key is the most important key in an entity/table
A primary key can be any set of attributes that uniquely identifies a tupple/row
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Which of the following statement is true?
A primary key is a minimal candidate key
A...
A foreign key is defined as a minimal super key that is new that does not...
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Which of the following describes referential integrity? A. A Primary Key of a relational table must...
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A Pages entity in a relational database for tracking web browsing has the following attributes: PageID (the primary key, an integer number, required), PageURL (text, maximum 255 characters, required), IPAddress (text, maximum 15 characters, required), ViewDateTime (date and time the page was viewed, required). (a) Write an SQL Data Definition Language command to create the table for this entity. (b) Write an SQL Data Definition Language command to add a column for a new attribute to this table: ViewDuration (duration...
QUESTION 1 What is the most common relationship within a relational database? Select the best answer...
QUESTION 1 What is the most common relationship within a relational database? Select the best answer from the following. One-To-One relationship. o One-To-Many relationship. Many-To-Many relationship. Zero-To-Zero relationship. QUESTION 2 What is an "entity'? Select the best answer from the following. An entity, for our purposes, is the same as a table in the database. An entity represents one of the columns in an individual table. There are no entities in a relational database. Entities are only part of NoSQL...
16. The primary key is selected from the: Group of answer choices composite keys. foreign keys....
16. The primary key is selected from the: Group of answer choices composite keys. foreign keys. candidate keys. surrogate keys. 17. "Delete Table" statement is used to remove a table definition and all the data, indexes, triggers, constraints and permission specifications for that table. Group of answer choices True False 18. Which of the following commands always affect one row at a time when it runs? Group of answer choices Drop Insert Delete Update 19. Data stored as an image...
D. Check that integrity constraints are addressed Document that all integrity constraints are considered in the...
D. Check that integrity constraints are addressed Document that all integrity constraints are considered in the design. Create checklists to ensure that all four levels of integrity constraint – domain, entity, referential, and user – have been addressed. For example, Entity integrity requires that each table contains a primary key that uniquely identifies each row in the table, preventing duplicate rows. Domain integrity requires that the data entered is appropriate. A domain is defined as the set of all unique...
6. With respect to database systems, which of the following statement(s) is (are) true? a. The...
6. With respect to database systems, which of the following statement(s) is (are) true? a. The physical view of data is how people conceptually organize and understand the relationships among data items. b. The DML builds the data dictionary, creates the database, describes logical views for each user, and specifies security constraints. c. A record layout shows the items stored in a file, including the type of data stored and both the order and length of the data fields. d....
(MMU) has decided to consolidate the functionality of three small overlapping database systems, which support applications...
(MMU) has decided to consolidate the functionality of three small overlapping database systems, which support applications for 1) teaching (e.g. instructor assignment and evaluation), for 2) registration (e.g. online course status, waiting lists), and for 3) student records (e.g. transcript generation) The resulting new system will support the following enterprise description: Professors and GTAs are assigned to teach the sections of each class being offered in a semester. At the end of the semester, they get a "team rating" (professors...
The primary key for M:N relationship tables O is a single attribute. @ always consists of two attributes. O is the primary key of the most important entity linked to that relationship does not exist. Many-to-many relationship tables only use foreign keys
QUESTION 1 What is the most common relationship within a relational database? Select the best answer from the following. One-To-One relationship. o One-To-Many relationship. Many-To-Many relationship. Zero-To-Zero relationship. QUESTION 2 What is an "entity'? Select the best answer from the following. An entity, for our purposes, is the same as a table in the database. An entity represents one of the columns in an individual table. There are no entities in a relational database. Entities are only part of NoSQL...
6. With respect to database systems, which of the following statement(s) is (are) true? a. The physical view of data is how people conceptually organize and understand the relationships among data items. b. The DML builds the data dictionary, creates the database, describes logical views for each user, and specifies security constraints. c. A record layout shows the items stored in a file, including the type of data stored and both the order and length of the data fields. d....
(MMU) has decided to consolidate the functionality of three small overlapping database systems, which support applications for 1) teaching (e.g. instructor assignment and evaluation), for 2) registration (e.g. online course status, waiting lists), and for 3) student records (e.g. transcript generation) The resulting new system will support the following enterprise description: Professors and GTAs are assigned to teach the sections of each class being offered in a semester. At the end of the semester, they get a "team rating" (professors...
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