SQL Exercise: List all the employees of grade 2 and 3

Last update on December 20 2024 11:41:13 (UTC/GMT +8 hours)

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5. From the following table, write a SQL query to find the employees of grade 2 and 3.Return all the information of employees and salary details.

Sample table: employees

Sample table: salary_grade

Sample Solution:

SELECT *
FROM employees e,
     salary_grade s
WHERE e.salary BETWEEN s.min_sal AND s.max_sal
  AND s.grade IN (2, 3);

Sample Output:

 emp_id | emp_name | job_name | manager_id | hire_date  | salary  | commission | dep_id | grade | min_sal | max_sal
--------+----------+----------+------------+------------+---------+------------+--------+-------+---------+---------
  64989 | ADELYN   | SALESMAN |      66928 | 1991-02-20 | 1700.00 |     400.00 |   3001 |     3 |    1501 |    2100
  65271 | WADE     | SALESMAN |      66928 | 1991-02-22 | 1350.00 |     600.00 |   3001 |     2 |    1301 |    1500
  66564 | MADDEN   | SALESMAN |      66928 | 1991-09-28 | 1350.00 |    1500.00 |   3001 |     2 |    1301 |    1500
  68454 | TUCKER   | SALESMAN |      66928 | 1991-09-08 | 1600.00 |       0.00 |   3001 |     3 |    1501 |    2100
  69324 | MARKER   | CLERK    |      67832 | 1992-01-23 | 1400.00 |            |   1001 |     2 |    1301 |    1500
(5 rows)

Explanation:

The said query in SQL that retrieves all employees whose salary falls within the salary range of salary grades 2 and 3 from the 'employees' and 'salary_grade' tables.

The query uses an implicit join to combine the 'employees' and 'salary_grade' tables based on the "salary" and the "min_sal" and "max_sal" columns.

The query then filters the rows by applying the conditions are as follows:

The employee's salary falls within the range defined by the minimum and maximum salary values for each salary grade.

The salary grade is either 2 or 3.

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