Suppose R(A,B) is a relation schema with no constraints. Currently, R has 3 tuples: (1,2), (2,3), and (3,4 Consider the trigger Easy defined as follows: CREATE TRIGGER Easy AFTER UPDATE ON R REFERENCING OLD ROWS AS OldRow NEW ROWS AS NewRow FOR EACH ROW WHEN (NewRow.B < 10) INSERT INTO R VALUES (NewRow.A, 1+NewRow.B); If we execute the following transaction and the trigger, what is the set of tuples in R? UPDATE R SET B = B+7 WHERE A < 3;

Suppose R(A,B) is a relation schema with no constraints. Currently, R has 3 tuples: (1,2), (2,3), and (3,4 Consider the trigger Easy defined as follows: CREATE TRIGGER Easy AFTER UPDATE ON R REFERENCING OLD ROWS AS OldRow NEW ROWS AS NewRow FOR EACH ROW WHEN (NewRow.B < 10) INSERT INTO R VALUES (NewRow.A, 1+NewRow.B); If we execute the following transaction and the trigger, what is the set of tuples in R? UPDATE R SET B = B+7 WHERE A < 3;

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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