"MySQL: each chapter homework answers"

DQL language learning _ the underlying query:

# 1. The following statement is executed successfully

SELECT last_name , job_id , salary AS sal FROM employees;

# 2. The following statement is executed successfully

SELECT * FROM employees;

# 3 Find out the following statement in error
# error

SELECT employee_id , last_name，salary * 12 “ANNUAL SALARY”FROM employees;

#correct

SELECT employee_id , last_name,salary * 12 "ANNUAL SALARY" FROM employees;

# 4. Table shows the structure of the departments, and wherein all the data of the query

DESC departme