Syntax
------ 
MIN([DISTINCT] expr)
 
Description
----------- 
Returns the minimum value of expr. MIN() may take a string
argument, in which case it returns the minimum string value.
The DISTINCT
keyword can be used to find the minimum of the distinct
values of expr,
however, this produces the same result as omitting DISTINCT.
 
Note that SET and ENUM fields are currently compared by
their string value rather than their relative position in
the set, so MIN() may produce a different lowest result than
ORDER BY ASC.
 
It is an aggregate function, and so can be used with the
GROUP BY clause.
 
From MariaDB 10.2.2, MIN() can be used as a window function.
 
MIN() returns NULL if there were no matching rows.
 
Examples
-------- 
CREATE TABLE student (name CHAR(10), test CHAR(10), score
TINYINT); 
 
INSERT INTO student VALUES 
 ('Chun', 'SQL', 75), ('Chun', 'Tuning', 73), 
 ('Esben', 'SQL', 43), ('Esben', 'Tuning', 31), 
 ('Kaolin', 'SQL', 56), ('Kaolin', 'Tuning', 88), 
 ('Tatiana', 'SQL', 87), ('Tatiana', 'Tuning', 83);
 
SELECT name, MIN(score) FROM student GROUP BY name;
 
+---------+------------+
| name | MIN(score) |
+---------+------------+
| Chun | 73 |
| Esben | 31 |
| Kaolin | 56 |
| Tatiana | 83 |
+---------+------------+
 
MIN() with a string:
 
SELECT MIN(name) FROM student;
 
+-----------+
| MIN(name) |
+-----------+
| Chun |
+-----------+
 
Be careful to avoid this common mistake, not grouping
correctly and returning mismatched data: 
 
SELECT name,test,MIN(score) FROM student;
 
+------+------+------------+
| name | test | MIN(score) |
+------+------+------------+
| Chun | SQL | 31 |
+------+------+------------+
 
Difference between ORDER BY ASC and MIN():
 
CREATE TABLE student2(name CHAR(10),grade
ENUM('b','c','a'));
 
INSERT INTO student2
VALUES('Chun','b'),('Esben','c'),('Kaolin','a');
 
SELECT MIN(grade) FROM student2;
 
+------------+
| MIN(grade) |
+------------+
| a |
+------------+
 
SELECT grade FROM student2 ORDER BY grade ASC LIMIT 1;
 
+-------+
| grade |
+-------+
| b |
+-------+
 
As a window function:
 
CREATE OR REPLACE TABLE student_test (name CHAR(10), test
CHAR(10), score TINYINT);
INSERT INTO student_test VALUES 
 ('Chun', 'SQL', 75), ('Chun', 'Tuning', 73), 
 ('Esben', 'SQL', 43), ('Esben', 'Tuning', 31), 
 ('Kaolin', 'SQL', 56), ('Kaolin', 'Tuning', 88), 
 ('Tatiana', 'SQL', 87);
 
SELECT name, test, score, MIN(score) 
 OVER (PARTITION BY name) AS lowest_score FROM student_test;
 
+---------+--------+-------+--------------+
| name | test | score | lowest_score |
+---------+--------+-------+--------------+
| Chun | SQL | 75 | 73 |
| Chun | Tuning | 73 | 73 |
| Esben | SQL | 43 | 31 |
| Esben | Tuning | 31 | 31 |
| Kaolin | SQL | 56 | 56 |
| Kaolin | Tuning | 88 | 56 |
| Tatiana | SQL | 87 | 87 |
+---------+--------+-------+--------------+
 


URL: https://mariadb.com/kb/en/min/