# MAX

## Syntax

```sql
MAX([DISTINCT] expr)
```

## Description

Returns the largest, or maximum, value of *`expr`*. `MAX()` can also take a string argument in which case it returns the maximum string value. The `DISTINCT` keyword can be used to find the maximum of the distinct values of *`expr`*, however, this produces the same result as omitting `DISTINCT`.

Note that [SET](/docs/server/reference/sql-statements/administrative-sql-statements/set-commands/set.md) and [ENUM](/docs/server/reference/data-types/string-data-types/enum.md) fields are currently compared by their string value rather than their relative position in the set, so MAX() may produce a different highest result than ORDER BY DESC.

It is an [aggregate function](/docs/server/reference/sql-functions/aggregate-functions.md), and so can be used with the [GROUP BY](/docs/server/reference/sql-statements/data-manipulation/selecting-data/group-by.md) clause.

MAX() can be used as a [window function](/docs/server/reference/sql-functions/special-functions/window-functions.md).

`MAX()` returns `NULL` if there were no matching rows.

{% tabs %}
{% tab title="Current" %}
Not only ascending, but also [descending indexes](/docs/server/server-usage/tables/create-table.md#index-types) can be used to optimize `MAX`.
{% endtab %}

{% tab title="< 11.4" %}
Only ascending indexes can be used to optimize `MAX`.
{% endtab %}
{% endtabs %}

## Examples

```sql
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, MAX(score) FROM student GROUP BY name;
+---------+------------+
| name    | MAX(score) |
+---------+------------+
| Chun    |         75 |
| Esben   |         43 |
| Kaolin  |         88 |
| Tatiana |         87 |
+---------+------------+
```

`MAX` string:

```sql
SELECT MAX(name) FROM student;
+-----------+
| MAX(name) |
+-----------+
| Tatiana   |
+-----------+
```

Be careful to avoid this common mistake, not grouping correctly and returning mismatched data:

```sql
SELECT name,test,MAX(SCORE) FROM student;
+------+------+------------+
| name | test | MAX(SCORE) |
+------+------+------------+
| Chun | SQL  |         88 |
+------+------+------------+
```

Difference between `ORDER BY DESC` and `MAX()`:

```sql
CREATE TABLE student2(name CHAR(10),grade ENUM('b','c','a'));

INSERT INTO student2 VALUES('Chun','b'),('Esben','c'),('Kaolin','a');

SELECT MAX(grade) FROM student2;
+------------+
| MAX(grade) |
+------------+
| c          |
+------------+

SELECT grade FROM student2 ORDER BY grade DESC LIMIT 1;
+-------+
| grade |
+-------+
| a     |
+-------+
```

As a [window function](/docs/server/reference/sql-functions/special-functions/window-functions.md):

```sql
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, MAX(score) 
  OVER (PARTITION BY name) AS highest_score FROM student_test;
+---------+--------+-------+---------------+
| name    | test   | score | highest_score |
+---------+--------+-------+---------------+
| Chun    | SQL    |    75 |            75 |
| Chun    | Tuning |    73 |            75 |
| Esben   | SQL    |    43 |            43 |
| Esben   | Tuning |    31 |            43 |
| Kaolin  | SQL    |    56 |            88 |
| Kaolin  | Tuning |    88 |            88 |
| Tatiana | SQL    |    87 |            87 |
+---------+--------+-------+---------------+
```

## See Also

* [AVG](/docs/server/reference/sql-functions/aggregate-functions/avg.md) (average)
* [MIN](/docs/server/reference/sql-functions/aggregate-functions/min.md) (minimum)
* [SUM](/docs/server/reference/sql-functions/aggregate-functions/sum.md) (sum total)
* [GREATEST()](/docs/server/reference/sql-structure/operators/comparison-operators/greatest.md) returns the largest value from a list

<sub>*This page is licensed: GPLv2, originally from*</sub> [<sub>*fill\_help\_tables.sql*</sub>](https://github.com/MariaDB/server/blob/main/scripts/fill_help_tables.sql)

{% @marketo/form formId="4316" %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://mariadb.com/docs/server/reference/sql-functions/aggregate-functions/max.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.