The command select count(*) from departments; returns 28. How many rows does the following command return? select * from departments where manager_id = NULL; 28 0 It depends on the values of manager_id in roes The command causes an error because we cannot use the equal sign with NULL

The command select count() from departments; returns 28. How many rows does the following command return? select from departments where manager_id = NULL; 28 0 It depends on the values of manager_id in roes The command causes an error because we cannot use the equal sign with NULL

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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Please give me correct solution with explanation. The DATE option of the COLUMN command does not allow a specific format to be applied to date values. True False