**************** Basic SELECT statement

1. Write a query to display the names (first_name, last_name) using

alias name “First Name", "Last Name"
R= select first_name "First Name", last_name "Last Name" from employees limit 20;

2. Write a query to get unique department ID from employee table.

R= select distinct dept_no from dept_emp limit 20;

3. Write a query to get all employee details from the employee table
order by first name, descending
R= select * from employees order by first_name desc limit 20;
 4. Write a query to get the names (first_name, last_name), salary, PF
of all the employees (PF is calculated as 15% of salary).
R= select employees.emp_no, first_name, last_name, salary, salary*.15 ‘pf’ from
employees inner join employees.emp_no=salaries.emp_no limit 20;

5. Write a query to get the employee ID, names (first_name,

last_name), salary in ascending order of salary.
R= select employees.emp_no, first_name, last_name, salary from employees inner
join employees.emp_no=salaries.emp_no order by salary asc limit 20;

6. Write a query to get the total salaries payable to employees.

R= select sum(salary) as ‘Total Salaries’ from salaries;
 7. Write a query to get the maximum and minimum salary from
employees table.
R= select min(salary), max(salary) from salaries;

8. Write a query to get the average salary and number of employees in

the employees table.
R= select max(emp_no), avg(salary) from salaries;

9. Write a query to get the number of employees working with the

company.
R= select count(emp_no) from employees;

10. Write a query to get the number of jobs available in the employees
table.
R= select count(dept_name) ‘Number of Jobs’ from departments;

11. Write a query get all first name from employees table in upper case.
R= select upper(first_name) from employees limit 20;
 12. Write a query to get the first 3 characters of first name from
employees table.
R= select first_name from employees limit 3 limit 20;

13. Write a query to calculate 171*214+625.

R= SELECT 171*214+625 Result;

14. Write a query to get the names (for example Ellen Abel, Sundar Ande
etc.) of all the employees from employees table.
R= select concat(first_name,' ', last_name) 'employee name' from
employees limit 20;
15. Write a query to get first name from employees table after removing
white spaces from both side.
R= select trim(first_name) from employees limit 20;

16. Write a query to get the length of the employee names (first_name,
last_name) from employees table.
R= select first_name,last_name, length(first_name)+length(last_name)
'length of names' from employees limit 20;

17. Write a query to check if the first_name fields of the employees table
contains numbers.
R= select * from employees where first_name regexp '[0-9]';

18. Write a query to select first 10 records from a table.

R= select employee_id, first_name from employees limit 10;
19. Write a query to get monthly salary (round 2 decimal places) of each
and every employee
R= select employees.emp_no , first_name, last_name, salary,
round(salary/12,2) ‘Monthly Salary’ from employees inner join salaries on
employees.emp_no=salaries.emp_no limit 20;

***************** Restricting and Sorting data

1. Write a query to display the name (first_name, last_name) and
salary for all employees whose salary is not in the range $10,000
through $15,000
R= select employees.emp_no, first_name, last_name, salary from
employees inner join salaries on employees.emp_no=salaries.emp_no
where salary not between 10000 and 15000 limit 20;
 2. Write a query to display the name (first_name, last_name) and
department ID of all employees in departments 30 or 100 in
ascending order.
R= select employees.emp_no, first_name, last_name, dept_no from
employees inner join dept_emp on employees.emp_no=dept_emp.emp_no
where dept_no in(‘d001’, ‘d003’) order by dept_no asc limit 20;

En el ejemplo use de d001 a d003 para que me arrojara algún resultado.

3. Write a query to display the name (first_name, last_name) and
salary for all employees whose salary is not in the range $10,000
through $15,000 and are in department 30 or 100.
R= select first_name, last_name, dept_no, salary from employees inner
join dept_emp on employees.emp_no=dept_emp.emp_no inner join
salaries on salaries.emp_no where dept_no in(‘d006’,’d008’) and salary
not between 10000 and 15000 limit 20;

En el ejemplo use de d003 a d008 para que me arrojara algún resultado.

 4. Write a query to display the name (first_name, last_name) and hire
date for all employees who were hired in 1987.
R= select employees.emp_no, first_name, last_name, from_date from
employees inner join dept_emp_latest_date on
employees.emp_no=dept_emp_latest_date.emp_no where
year(from_date) like ‘1987%’ limit 20;

5. Write a query to display the first_name of all employees who have

both "b" and "c" in their first name.
R= select first_name from employees where first_name like ‘%b%’ and
first_name like ‘%c%’ limit 20;
 6. Write a query to display the last name, job, and salary for all
employees whose job is that of a Programmer or a Shipping Clerk,
and whose salary is not equal to $4,500, $10,000, or $15,000.
R= select last_name, title, salary from employees inner join salaries on
salaries.emp_no inner join titles on employees.emp_no=titles.emp_no
where title in(‘Staff’,’Engineer’) and salary not in(4500, 10000, 15000) limit
20;

En el ejemplo use de d003 a d008 para que me arrojara algún resultado.

7. Write a query to display the last name of employees whose names
have exactly 6 characters.
R= select first_name as ‘Nombres de seis letras’, last_name from
employees where length(first_name)=6 limit 20;
 8. Write a query to display the last name of employees having 'e' as
the third character.
R= select last_name from employees where last_name like ‘__e%’ limit 20;

9. Write a query to display the jobs/designations available in the

employees table.
R= select * from departments;

10. Write a query to display the name (first_name, last_name), salary

and PF (15% of salary) of all employees.
R= select employees.emp_no first_name , last_name, salary, salary*.15 as
‘PF’ from employees inner join salaries on
salaries.emp_no=salaries.emp_no limit 20;
 11. Write a query to select all record from employees where last name
in 'BLAKE', 'SCOTT', 'KING' and 'FORD'.
R= select * from employees where last_name
in(‘blake’,’scott’,’king’,’ford’);

******************* Aggregate Functions and Group by

1. Write a query to list the number of jobs available in the employees

table.
R= select count(dept_name) from departments;

2. Write a query to get the total salaries payable to employees.

R= select sum(salary) from salaries;

3. Write a query to get the minimum salary from employees table.

R= select min(salary) from salaries;

4. Write a query to get the maximum salary of an employee working as

a Programmer.
R= select max(salary), dept_no from salaries inner join dept_emp on
salaries.emp_no=dept_emp.emp_no where dept_no=’d001’;
 5. Write a query to get the average salary and number of employees
working the department 90.
R= select avg(salary), dept_no from salaries inner join dept_emp on
salaries.emp_no=dept_emp.emp_no where dept_no=’d001’;

6. Write a query to get the highest, lowest, sum, and average salary of
all employees.
R= select max(salary) as ‘max salary’, min(salary) as ‘min salary’,
sum(salary) as ‘sum’, avg(salary) as ‘prom’ from salaries;

7. Write a query to get the number of employees with the same job.
R= select dept_no, count(*) as ‘personas trabajando’ from dept_emp
group by dept_no;

8. Write a query to get the difference between the highest and lowest
salaries.
R= select max(salary), min(salary), max(salary)-min(salary from salaries;
 9. Write a query to find the manager ID and the salary of the lowest-
paid employee for that manager.
R= select min(salary, dept_no from dept_emp inner join salaries on
dept_emp.emp_no=salaries.emp_no group by dept_no limit 20;

10. Write a query to get the department ID and the total salary payable
in each department.
R= select sum(salary), dept_no from dept_emp inner join salaries on
dept_emp.emp_no=salaries.emp_no group by dept_no limit 20;

11. Write a query to get the average salary for each job ID excluding
programmer.
R= select avg(salary), dept_no from dept_emp inner join salaries on
dept_emp.emp_no=salaries.emp_no where dept_no not in(‘d001’) group
by dept_no limit 20;

se excluyo a marketing d001

 12. Write a query to get the total salary, maximum, minimum, average
salary of employees (job ID wise), for department ID 90 only.
R= select sum(salary), min(salary), max(salary), avg(salary), dept_no from
salaries inner join dept_emp on salaries.emp_no=dept_emp.emp_no
where dept_no=’d001’;

13. Write a query to get the job ID and maximum salary of the
employees where maximum salary is greater than or equal to $4000.
R= select max(salary), emp_no from salaries where salary >= 4000 group
by emp_no limit 20;

14. Write a query to get the average salary for all departments
employing more than 10 employees.
R= select amvg(salary), dept_no, count(*) as ‘numero empleados’ from
dept_emp inner join salaries on dept_emp.emp_no group by
dept_nonhaving count(*) >10;