This set of Database online test focuses on “Entity-Relationship Design Issues”. 1. Let us consider phone_number ,which can take single or several values . Treating phone_numberas an _________ permits instructors to have several phone numbers (including zero) associated with them. Answer: a 2. The total participation by entities is represented in E-R diagram as Answer: b 3. Given the basic ER and relational models, which of the following is INCORRECT? Answer: c 4. Which of the following indicates the maximum number of entities that can be involved in a relationship? Answer: b 5. In E-R diagram generalization is represented by Answer: d 6. What is a relationship called when it is maintained between two entities? Answer: b 7. Which of the following is a low level operator? Answer: d 8. Key to represent relationship between tables is called Answer: c 9. A window into a portion of a database is Answer: b 10. A primary key is combined with a foreign key creates Answer: a Sanfoundry Global Education & Learning Series – Database Management System. Next Steps:
 Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn. Subscribe to his free Masterclasses at Youtube & technical discussions at Telegram SanfoundryClasses. Use the equation x + x + 2 = 2x to complete parts (a) through (c). a. Build the equation on your Equation Mat and simplify it as much as possible. Record your steps and what you see when you have simplified the equation fully. Draw a picture of your final mat. b. Have each member of your team test a different value for x in the equation, such as x = 0, x = 1, x = -5, x = 10, etc. What happens? Is there a pattern to the results you get from the equation? c. Did you find any values for x that satisfied the equation in part (a)? When there is an imbalance of units left on the mat (such as 2 = 0), what does this mean? Is x = 0 a solution to the equation? Which of the following indicates the maximum number of entities that can be involved in a relationship options?4. Which of the following indicates the maximum number of entities that can be involved in a relationship? Explanation: In SQL (Structured Query Language), the term cardinality refers to the uniqueness of data values contained in a particular column (attribute) of a database table.
What is the term for the maximum number of entities that can participate in a relationship?These are called cardinality ratios. These represent the maximum number of entities that can be associated with each other through relationship, R. Types of Cardinality : There can be 4 types of cardinality –
What is the maximum number of entities?There actually could be 1000 entities, since each possible (A,C) pair (of which there are 1000) could appear in the set each with a different B (of which there are 10000) without violating the cardinality constraints. So the maximum number of entities is not smaller than 1000.
Which of the following indicates the minimum number of entities that can be involved in a relationship?Minimum cardinality: minimum number of entity instances that must participate in a relationship.
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Which of the following indicates the maximum number of entities can be involved in a relationship?
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