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.

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/