Modern Database Management
13th Edition
ISBN: 9780134773650
Author: Hoffer
Publisher: PEARSON
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Textbook Question
Chapter 5, Problem 5.17RQ
What is the difference between COUNT, COUNT DISTINCT, and COUNT(*) in SQL? When will these three commands generate the same and different results?
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Chapter 5 Solutions
Modern Database Management
Ch. 5 - Define each of the following terms: data...Ch. 5 - Match the following terms to the appropriate...Ch. 5 - Prob. 5.3RQCh. 5 - Prob. 5.4RQCh. 5 - Prob. 5.5RQCh. 5 - Prob. 5.6RQCh. 5 - List six potential benefits of achieving an SQL...Ch. 5 - Prob. 5.8RQCh. 5 - Distinguish among data definition commands, data...Ch. 5 - Prob. 5.10RQ
Ch. 5 - Prob. 5.11RQCh. 5 - Explain the purpose of indexing in database...Ch. 5 - What are the potential consequence of...Ch. 5 - Prob. 5.14RQCh. 5 - Explain and provide at least one example Of how to...Ch. 5 - Prob. 5.16RQCh. 5 - What is the difference between COUNT, COUNT...Ch. 5 - What is the evaluation order for the Boolean...Ch. 5 - If an SQL statement includes a GROUP BY clause,...Ch. 5 - Prob. 5.20RQCh. 5 - Prob. 5.21RQCh. 5 - Prob. 5.22RQCh. 5 - Explain why SQL is called a set-oriented language.Ch. 5 - When would the use of the LIKE key word with the...Ch. 5 - Prob. 5.25RQCh. 5 - Prob. 5.26RQCh. 5 - In what order are the clauses of an SQL statement...Ch. 5 - Within which clauses of an SQL statement can a...Ch. 5 - Prob. 5.29RQCh. 5 - Prob. 5.30RQCh. 5 - Prob. 5.31RQCh. 5 - Explain the difference between the WHERE and...Ch. 5 - Prob. 5.33RQCh. 5 - Write a database description for each of the...Ch. 5 - Analyze the database to determine whether or not...Ch. 5 - Prob. 5.36PAECh. 5 - To enforce referential integrity, before any row...Ch. 5 - Write SQL data definition commands for each of the...Ch. 5 - Write SQL commands for the following: Create two...Ch. 5 - Write SQL queries to answer the following...Ch. 5 - Write SQL queries to answer the following...Ch. 5 - Write SQL queries to answer the following...Ch. 5 - Write SQL queries to answer the following...Ch. 5 - Prob. 5.44PAECh. 5 - Prob. 5.45PAECh. 5 - Prob. 5.46PAECh. 5 - What is the average Read score for all students?...Ch. 5 - Prob. 5.48PAECh. 5 - What are the TutorIDs for tutors who have not yet...Ch. 5 - Prob. 5.50PAECh. 5 - Prob. 5.51PAECh. 5 - Prob. 5.52PAECh. 5 - Prob. 5.53PAECh. 5 - Prob. 5.54PAECh. 5 - How many tutors have an Active status in the...Ch. 5 - Prob. 5.56PAECh. 5 - Modify the Product_T table by adding an attribute...Ch. 5 - Enter sample data of your own choosing into...Ch. 5 - Add an order to the Order_T table and include a...Ch. 5 - Use the Pine Valley database to answer the...Ch. 5 - Prob. 5.61PAECh. 5 - Prob. 5.62PAECh. 5 - Prob. 5.63PAECh. 5 - Prob. 5.64PAECh. 5 - Prob. 5.65PAECh. 5 - Prob. 5.66PAECh. 5 - Prob. 5.67PAECh. 5 - Modify query in P&E 5-67 by considering only those...Ch. 5 - Prob. 5.69PAECh. 5 - Prob. 5.70PAECh. 5 - Prob. 5.71PAECh. 5 - Prob. 5.72PAECh. 5 - Prob. 5.73PAECh. 5 - Prob. 5.74PAECh. 5 - Prob. 5.75PAECh. 5 - Prob. 5.76PAECh. 5 - Prob. 5.77PAECh. 5 - Assume that for those materials the ID of which...Ch. 5 - Prob. 5.79PAECh. 5 - Prob. 5.80PAECh. 5 - Prob. 5.81PAECh. 5 - Prob. 5.82PAECh. 5 - Prob. 5.83PAECh. 5 - Prob. 5.84PAECh. 5 - Prob. 5.85PAECh. 5 - Prob. 5.86PAECh. 5 - Prob. 5.87PAECh. 5 - Prob. 5.88PAECh. 5 - Prob. 5.89PAECh. 5 - Prob. 5.90PAECh. 5 - Prob. 5.91PAECh. 5 - Prob. 5.92PAECh. 5 - Prob. 5.93PAE
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