Database Systems: Design, Implementation, & Management
12th Edition
ISBN: 9781305627482
Author: Carlos Coronel, Steven Morris
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Expert Solution & Answer
Chapter 8, Problem 21RQ
Explanation of Solution
Trigger:
The trigger is a named set of SQL statement that is executed at the time of data modification or meets some data description.
- If the stated when trigger condition meets up, then the mentioned action in the trigger has been performed.
There are three parts of trigger; they are:
Event:
- It specifies the change to be made, such as an UPDATE or DELETE of a record.
Condition:
- It specifies the condition to examine the records about to be affected. For each record, that meets the condition given in the trigger.
Action:
- The action performed after the start of the trigger.
The syntax to create a trigger is as given below:
CREATE TRIGGER trigger_name
{BEFORE| AFTER|INSTEAD OF} {INSERT|DELETE|UPDATE} ON
table_name
[FOR EACH{ROW|STATEMENT}] [WHEN(condition)]
<triggered SQL statement here>;
Purpose of trigger:
The purpose of trigger is given below:
- For enforcement of business or security constraints...
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
What is a trigger, and how is it used?
Since you have been hired to work on a database, you may decide whether to use a trigger or a process. When should one pull a trigger, and what are they?
Discuss the differences between triggers and stored procedures.
Chapter 8 Solutions
Database Systems: Design, Implementation, & Management
Ch. 8 - What is a cross join? Give an example of its...Ch. 8 - What three join types are included in the outer...Ch. 8 - Using tables named T1 and T2, write a query...Ch. 8 - Prob. 4RQCh. 8 - Prob. 5RQCh. 8 - Prob. 6RQCh. 8 - Prob. 7RQCh. 8 - What does it mean to say that SQL operators are...Ch. 8 - Prob. 9RQCh. 8 - Prob. 10RQ
Ch. 8 - Prob. 11RQCh. 8 - Prob. 12RQCh. 8 - Given the employee information in Question 11,...Ch. 8 - Prob. 14RQCh. 8 - Prob. 15RQCh. 8 - Prob. 16RQCh. 8 - What Oracle function should you use to calculate...Ch. 8 - Prob. 18RQCh. 8 - What string function should you use to list the...Ch. 8 - Prob. 20RQCh. 8 - Prob. 21RQCh. 8 - Prob. 22RQCh. 8 - Prob. 23RQCh. 8 - Prob. 24RQCh. 8 - Prob. 1PCh. 8 - Insert the data into the tables you created in...Ch. 8 - Prob. 3PCh. 8 - Prob. 4PCh. 8 - Prob. 5PCh. 8 - Prob. 6PCh. 8 - Prob. 7PCh. 8 - Prob. 8PCh. 8 - Prob. 9PCh. 8 - Modify the CUSTOMER table to include two new...Ch. 8 - Assuming that you completed Problem 10, write the...Ch. 8 - Assuming that the CUSTOMER table contains a...Ch. 8 - Write the query that lists the average age of your...Ch. 8 - Write the trigger to update the CUST_BALANCE in...Ch. 8 - Prob. 15PCh. 8 - Prob. 16PCh. 8 - Write a trigger to update the customer balance...Ch. 8 - Write a procedure to delete an invoice, giving the...Ch. 8 - Prob. 19PCh. 8 - Prob. 20PCh. 8 - Prob. 21PCh. 8 - Prob. 22PCh. 8 - Write a single SQL command to increase all price...Ch. 8 - Prob. 24PCh. 8 - Prob. 25PCh. 8 - Prob. 26PCh. 8 - Prob. 27PCh. 8 - Create a trigger named trg_line_total to write the...Ch. 8 - Create a trigger named trg_line_prod that...Ch. 8 - Create a stored procedure named prc_inv_amounts to...Ch. 8 - Create a procedure named prc_cus_balance_update...Ch. 8 - Modify the MODEL table to add the attribute and...Ch. 8 - Prob. 33PCh. 8 - Modify the CHARTER table to add the attributes...Ch. 8 - Write the sequence of commands required to update...Ch. 8 - Write the sequence of commands required to update...Ch. 8 - Write the command required to update the...Ch. 8 - Write the command required to update the...Ch. 8 - Write the command required to update the...Ch. 8 - Prob. 40PCh. 8 - Create a trigger named trg_char_hours that...Ch. 8 - Create a trigger named trg_pic_hours that...Ch. 8 - Create a trigger named trg_cust_balance that...Ch. 8 - Prob. 44PCh. 8 - Prob. 45PCh. 8 - Prob. 46PCh. 8 - Prob. 47PCh. 8 - Prob. 48PCh. 8 - Prob. 49PCh. 8 - Prob. 50PCh. 8 - Prob. 51PCh. 8 - Prob. 52PCh. 8 - Prob. 53PCh. 8 - Prob. 54PCh. 8 - Prob. 55PCh. 8 - Prob. 56PCh. 8 - Prob. 57PCh. 8 - Prob. 58PCh. 8 - Prob. 59PCh. 8 - Prob. 61PCh. 8 - Prob. 62PCh. 8 - Prob. 63PCh. 8 - Prob. 64PCh. 8 - Prob. 65PCh. 8 - Prob. 66PCh. 8 - Prob. 67PCh. 8 - Alter the DETAILRENTAL table to include a derived...Ch. 8 - Update the DETAILRENTAL table to set the values in...Ch. 8 - Alter the VIDEO table to include an attribute...Ch. 8 - Update the VID_STATUS attribute of the VIDEO table...Ch. 8 - Alter the PRICE table to include an attribute...Ch. 8 - Prob. 73CCh. 8 - Prob. 76C
Knowledge Booster
Learn more about
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
- Explain in your own words: a.) What is metadata? b.) What is result set metadata? c.) When is result set metadata useful?arrow_forwardHow are nulls defined? Which field is not capable of accepting null values? How come?arrow_forwardWhen do triggers occur, and what are their characteristics? I have no notion what function they serve. [How do I access a trigger's features in Access 2016?]arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- A Guide to SQLComputer ScienceISBN:9781111527273Author:Philip J. PrattPublisher:Course Technology Ptr
A Guide to SQL
Computer Science
ISBN:9781111527273
Author:Philip J. Pratt
Publisher:Course Technology Ptr