Question 3. . Consider the following two command C1 and C2 on the relation R from an SQL database: C1: drop table R; C2: delete from R; Which of the following statements is True? I. Both C1 and C2 delete the schema for R. II. C2 retains relation R, but deletes all tuples in R. III. C1 deletes not only all tuples of R, but also the schema for R.

Question 3. . Consider the following two command C1 and C2 on the relation R from an SQL database: C1: drop table R; C2: delete from R; Which of the following statements is True? I. Both C1 and C2 delete the schema for R. II. C2 retains relation R, but deletes all tuples in R. III. C1 deletes not only all tuples of R, but also the schema for R.

Database Systems: Design, Implementation, & Management

11th Edition

ISBN:9781285196145

Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel

Publisher:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel

Chapter10: Transaction Management And Concurrency Control

Section: Chapter Questions

Problem 1P

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Suppose that you are a manufacturer of product ABC, which is composed of parts A, B, and C. Each time a new product ABC is created, it must be added to the product inventory, using the PROD_QOH in a table named PRODUCT. Also, each time the product is created, the parts inventory, using PART_QOH in a table named PART, must be reduced by one each of parts A, B, and C. The sample database contents are shown in Table P10.1. Given the preceding information, answer Questions a through e. How many database requests can you identify for an inventory update for both PRODUCT and PART? Using SQL, write each database request you identified in Step a. Write the complete transaction(s). Write the transaction log, using Table 10.1 as your template. Using the transaction log you created in Step d, trace its use in database recovery.
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