MySQL Exercise: Display the name and department ID of all employees for department 30 or 100 in ascending order
MySQL Restricting and Sorting Data: Exercise-2 with Solution
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.
Sample table: employees
+-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+ | EMPLOYEE_ID | FIRST_NAME | LAST_NAME | EMAIL | PHONE_NUMBER | HIRE_DATE | JOB_ID | SALARY | COMMISSION_PCT | MANAGER_ID | DEPARTMENT_ID | +-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+ | 100 | Steven | King | SKING | 515.123.4567 | 1987-06-17 | AD_PRES | 24000.00 | 0.00 | 0 | 90 | | 101 | Neena | Kochhar | NKOCHHAR | 515.123.4568 | 1987-06-18 | AD_VP | 17000.00 | 0.00 | 100 | 90 | | 102 | Lex | De Haan | LDEHAAN | 515.123.4569 | 1987-06-19 | AD_VP | 17000.00 | 0.00 | 100 | 90 | | 103 | Alexander | Hunold | AHUNOLD | 590.423.4567 | 1987-06-20 | IT_PROG | 9000.00 | 0.00 | 102 | 60 | | 104 | Bruce | Ernst | BERNST | 590.423.4568 | 1987-06-21 | IT_PROG | 6000.00 | 0.00 | 103 | 60 | | 105 | David | Austin | DAUSTIN | 590.423.4569 | 1987-06-22 | IT_PROG | 4800.00 | 0.00 | 103 | 60 | | 106 | Valli | Pataballa | VPATABAL | 590.423.4560 | 1987-06-23 | IT_PROG | 4800.00 | 0.00 | 103 | 60 | | 107 | Diana | Lorentz | DLORENTZ | 590.423.5567 | 1987-06-24 | IT_PROG | 4200.00 | 0.00 | 103 | 60 | | 108 | Nancy | Greenberg | NGREENBE | 515.124.4569 | 1987-06-25 | FI_MGR | 12000.00 | 0.00 | 101 | 100 | ......... | 206 | William | Gietz | WGIETZ | 515.123.8181 | 1987-10-01 | AC_ACCOUNT | 8300.00 | 0.00 | 205 | 110 | +-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+
Code:
-- Selecting the first_name, last_name, and department_id columns
SELECT first_name, last_name, department_id
-- Selecting data from the employees table
FROM employees
-- Filtering the result set to include only rows where the department_id is either 30 or 100
WHERE department_id IN (30, 100)
-- Ordering the result set by the department_id column in ascending order
ORDER BY department_id ASC;
Explanation:
- This SQL query selects the first_name, last_name, and department_id columns from the employees table.
- The WHERE clause filters the result set to include only those rows where the department_id column matches either 30 or 100.
- The IN operator is used to specify multiple values for filtering.
- The ORDER BY clause sorts the result set by the department_id column in ascending order (ASC is optional here since it's the default).
- This query is useful when you want to retrieve employees who belong to specific departments and order them by department ID.
Relational Algebra Expression:
Relational Algebra Tree:
Pictorial Presentation of the above query
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PREV :Write a query to display the names (first_name, last_name) and salary for all employees whose salary is not in the range $10,000 through $15,000.
NEXT :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.
MySQL Code Editor:
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