UPPER
Overview
The UPPER()
function returns a given string, an expression, or values in a column in all uppercase letters. The syntax of the function is illustrated below:
UPPER(string)
It accepts input as a string and returns text in uppercase letters.
đź’ˇ Special Case:
-
If characters in the input are not of type string, they remain unaffected by the
UPPER()
function. -
We support Unicode for the
UPPER()
function.
Examples
#Case 1: Basic UPPER()
function
The following basic query converts the given string in all uppercase alphabets:
SELECT UPPER('PostGreSQL');
The final output will be as follows:
+-------------+
| upper |
+-------------+
| POSTGRESQL |
+-------------+
#Case 2: UPPER() function using columns and CONCAT() function
Let’s see how the UPPER()
function works using an example with columns. We have a table named personal_details containing employee’s id, first_name, last_name, and gender of a retail store:
CREATE TABLE personal_details (
id int,
first_name string,
last_name string,
gender string
);
INSERT INTO personal_details
(id, first_name, last_name, gender)
VALUES
(1,'Mark','Wheeler','M'),
(2,'Tom','Hanks','M'),
(3,'Jane','Hopper','F'),
(4,'Emily','Byers','F'),
(5,'Lucas','Sinclair','M');
SELECT * FROM personal_details;
The above query will show the following table:
+-----+-------------+-------------+----------+
| id | first_name | last_name | gender |
+-----+-------------+-------------+----------+
| 1 | Mark | Wheeler | M |
| 2 | Tom | Hanks | M |
| 3 | Jane | Hopper | F |
| 4 | Emily | Byers | F |
| 5 | Lucas | Sinclair | M |
+-----+-------------+-------------+----------+
Let’s assume that:
-
We want to convert employees’ first and last names with id numbers 1, 3, and 5 to all uppercase letters.
-
Then, combine them using the
CONCAT()
function into one full_name column in uppercase.
It can be done using the following query:
SELECT CONCAT (UPPER(first_name),' ', UPPER(last_name))
as full_name
FROM personal_details
where id in (1, 3, 5);
The output displays the first and last names of employees with the specified ids in uppercase letters:
+---------------------+
| full_name |
+---------------------+
| MARK WHEELER |
| JANE HOPPER |
| LUCAS SINCLAIR |
+---------------------+