Refer to the sample tables and sample data below.Tables:adult (id(pk), name)child (id(pk), name)parent_child (parent (pk, fk), child (pk, fk))foreign key (parent) references adult(id)- foreign key (child) references child(id)mysql> SELECT * FROM adult;|id|name|1 | Homer Simpson.| 2 | Marge Simpson||||||3 | Fred Flintstone4 | Wilma Flintstone5 | George Jetson6 | Jane Jetson7 | Patty Bouvier8 | Selma Bouviermysql> SELECT * FROM child;|id|name| 11 | Bart| 12 | Lisa| 13 | Maggie| 14 |Pebbles| 15 | Judy| 16 | Elroy| 17 | Lingmysql> SELECT * FROM parent_child;| parent child |1 |2 |1 |21 |213 |45 |in 10 in65 |10001111121213 |131414 |815556615 |6 | 161716 | (a) How many rows will be returned by the following command? [Select]SELECT DISTINCT a.name FROM adult aLEFT JOIN parent_child pc ON a.id = pc.parentLEFT JOIN child c ON pc.child = c.id;(b) How many rows will be returned by the following command? [Select]SELECT DISTINCT a.name FROM adult aRIGHT JOIN parent_child pc ON a.id = pc.parentRIGHT JOIN child c ON pc.child = c.id;

Please find the answer in the following steps.

(a) How many rows will be returned by the following command? [Select] SELECT DISTINCT a.name FROM adult a LEFT JOIN parent_child pc ON a.id = pc.parent LEFT JOIN child c ON pc.child = c.id; (b) How many rows will be returned by the following command? [Select] SELECT DISTINCT a.name FROM adult a RIGHT JOIN parent_child pc ON a.id = pc.parent RIGHT JOIN child c ON pc.child = c.id; <

(a) How many rows will be returned by the following command? [Select] SELECT DISTINCT a.name FROM adult a LEFT JOIN parent_child pc ON a.id = pc.parent LEFT JOIN child c ON pc.child = c.id; (b) How many rows will be returned by the following command? [Select] SELECT DISTINCT a.name FROM adult a RIGHT JOIN parent_child pc ON a.id = pc.parent RIGHT JOIN child c ON pc.child = c.id; <

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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