Database Concepts (7th Edition)
7th Edition
ISBN: 9780133544626
Author: David M. Kroenke, David J. Auer
Publisher: PEARSON
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Chapter 2, Problem 2.11RQ
Explanation of Solution
Non-Unique key:
A non-unique key is the key which identifies more than one fields identified from the
- It produces the duplicate entries on the database table.
Example:
Let us consider a “student ...
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How can key distribution be accomplished? Please provide an example.
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using public key algorithm.
Give an example of a primary key
Chapter 2 Solutions
Database Concepts (7th Edition)
Ch. 2 - Prob. 2.1RQCh. 2 - Define the term entity, and give an example of an...Ch. 2 - Prob. 2.3RQCh. 2 - Prob. 2.4RQCh. 2 - Prob. 2.5RQCh. 2 - Prob. 2.6RQCh. 2 - Prob. 2.7RQCh. 2 - Prob. 2.8RQCh. 2 - Prob. 2.9RQCh. 2 - Define the term unique key and give an example.
Ch. 2 - Prob. 2.11RQCh. 2 - Prob. 2.12RQCh. 2 - Prob. 2.13RQCh. 2 - Describe four uses of a primary key.Ch. 2 - Prob. 2.15RQCh. 2 - Prob. 2.16RQCh. 2 - Prob. 2.17RQCh. 2 - Explain the term foreign key, and give an example.Ch. 2 - Prob. 2.19RQCh. 2 - Prob. 2.20RQCh. 2 - Explain three possible interpretations of a null...Ch. 2 - Give an example of a null value (other than one...Ch. 2 - Prob. 2.23RQCh. 2 - Prob. 2.24RQCh. 2 - Prob. 2.25RQCh. 2 - Prob. 2.26RQCh. 2 - Prob. 2.27RQCh. 2 - Define the term primary key in terms of functional...Ch. 2 - Prob. 2.31RQCh. 2 - Examine the data in the Veterinary Office...Ch. 2 - Prob. 2.33RQCh. 2 - Describe a modification problem that occurs when...Ch. 2 - Prob. 2.35RQCh. 2 - Prob. 2.36RQCh. 2 - Prob. 2.37RQCh. 2 - Apply the normalization process to the Veterinary...Ch. 2 - Prob. 2.39ECh. 2 - Prob. 2.40E
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.Similar questions
- Relational Database A relation R is given which is R(A,B,C,D,E). It has the following functional dependencies: BC -> E, E -> A and B -> D. Answer the following based on this information. Find all the candidate keys. What type of dependencies are found in this relation? Which normal form does this relation satisfy? Is it in 3NF? If not, decompose it until 3NFarrow_forwardCan you give example about composite key and alternate key ?arrow_forwardRelation. Questionarrow_forward
- Sec course is an example of a link that may be built from a collection of many-to-one connections. It's possible that the main and foreign key restrictions enforce the relation's many-to-one cardinality limitation. Is there a reason for this?arrow_forwardThe use of a surrogate key for the main key of a connection has been explained in three cases.arrow_forwardDatabase Systems Each branch of the Jaja restaurant has a mainstay menu that is very popular with customers, so information on the availability of the number of servings is needed to be able to serve orders. Here are two transactions that are ordering a food menu at the same time. T1: Start the transaction at time t1, read 10 servings of food stock at t2. Because ordering one portion, the stock is reduced by 1 at t3. On t6, update the stock count, and commit to t7. T2: Transaction T2 starts a transaction on t2, reads the number of stocks in t3 as many as 10. At t4 orders 3 portions. On t5 it updates the stock to 7 and then on t6 commits it. As a result of the T1 and T2 transactions above, there was an error in the amount of food stocks. Make a solution with 2PL. What kinds of problems happened? Give a reason why choosing this type of problem! How much food is still available?arrow_forward
- 2NF and 3NF define key-based generic entities differently. Please illustrate.arrow_forwardExplain the difference between Primary Key and Foreign Key , give examplearrow_forwardMany one-to-many connections may be pieced together to form a connection like the second track. Do the constraints of having a primary and foreign key impose the many-to-one cardinality limitation on the relation? Can you explain why you think that?arrow_forward
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