PostgreSQL String() Function: Find all the employees which first name contains all the uppercase letter

8. Write a query to find all the employees which first name contains all the uppercase letter.

Sample Solution:

Code:

-- This SQL query retrieves all columns from the employees table where the first name is in uppercase.

SELECT * -- Selects all columns from the employees table
FROM employees -- Specifies the table from which to retrieve data, in this case, the employees table
WHERE first_name = UPPER(first_name); -- Filters the rows to include only those where the first name is in uppercase

Explanation:

• This SQL query retrieves data from the employees table.
• The SELECT * statement selects all columns from the employees table.
• The FROM clause specifies the table from which to retrieve the data, which is the employees table.
• The WHERE clause filters the rows to include only those where the first_name column is equal to its uppercase version.
• The UPPER() function converts the first_name column to uppercase.
• The condition first_name = UPPER(first_name) checks if the first_name column is equal to its uppercase version, indicating that the first name is already in uppercase.
• The result set will contain all columns for rows where the first name is in uppercase.

Sample table: employees

Output:

pg_exercises=# SELECT *
pg_exercises-# FROM employees
pg_exercises-# WHERE first_name = UPPER(first_name);

 employee_id | first_name | last_name |     email     | phone_number | hire_date  |  job_id  | salary  | commission_pct | manager_id | department_id
-------------+------------+-----------+---------------+--------------+------------+----------+---------+----------------+------------+---------------
         132 | TJ         | Olson     | not available | 650.123.8234 | 1987-07-19 | ST_CLERK | 2130.00 |           0.10 |        121 |            50
(1 row)

(END)

Practice Online

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a query to get the employee id, email id to discard the last three characters.
Next: Write a query to extract the last four characters of phone numbers.