In MariaDB, MIN() is an aggregate function that returns the minimum value in a given expression.

Syntax

The syntax goes like this:

MIN([DISTINCT] expr)

Sample Data

Suppose we have a table with the following data:

SELECT
    VendorId,
    ProductName,
    ProductPrice
FROM Products;

Result:

+----------+---------------------------------+--------------+
| VendorId | ProductName                     | ProductPrice |
+----------+---------------------------------+--------------+
|     1001 | Left handed screwdriver         |        25.99 |
|     1001 | Right handed screwdriver        |        25.99 |
|     1001 | Long Weight (blue)              |        14.75 |
|     1001 | Long Weight (green)             |        11.99 |
|     1002 | Sledge Hammer                   |        33.49 |
|     1003 | Chainsaw                        |       245.00 |
|     1003 | Straw Dog Box                   |        55.99 |
|     1004 | Bottomless Coffee Mugs (4 Pack) |         9.99 |
+----------+---------------------------------+--------------+

Example

We can use the following query to get the minimum price from that table.

SELECT MIN(ProductPrice)
FROM Products;

Result:

9.99

In this case, price information is stored in the ProductPrice column, and so we pass that as an argument to the MIN() function, which then calculates and returns the result.

Filtered Results

The MIN() function operates on the rows returned by the query. So if you filter the results, the output of MIN() will reflect that.

SELECT MIN(ProductPrice)
FROM Products
WHERE VendorId = 1001;

Result:

11.99

In this case, 11.99 is the minimum price out of all the products offered by the specified vendor.

Date/Time Data

You can use MIN() on date/time values.

Suppose we have the following table:

SELECT PetName, DOB 
FROM Pets;

Result:

+---------+------------+
| PetName | DOB        |
+---------+------------+
| Fluffy  | 2020-11-20 |
| Fetch   | 2019-08-16 |
| Scratch | 2018-10-01 |
| Wag     | 2020-03-15 |
| Tweet   | 2020-11-28 |
| Fluffy  | 2020-09-17 |
| Bark    | NULL       |
| Meow    | NULL       |
+---------+------------+

We can use MIN() to find the minimum date of birth (DOB).

SELECT MIN(DOB)
FROM Pets;

Result:

2018-10-01

This would be the date of birth of the oldest pet.

NULL Values

The MIN() function ignores any NULL values. In our sample table above, the last two rows contain NULL values in their DOB column, but they were ignored in our MIN() example.

Character Data

When used with character data columns, MIN() finds the value that is lowest in the collating sequence.

Example:

SELECT MIN(ProductName)
FROM Products;

Result:

Bottomless Coffee Mugs (4 Pack)

The DISTINCT Keyword

The DISTINCT keyword can be used with the MIN() function, however, this produces the same result as omitting DISTINCT. Allowing the DISTINCT function enables MariaDB to comply with the ISO SQL standard.

Therefore, we can do this:

SELECT MIN(DISTINCT ProductPrice)
FROM Products;

Result:

9.99

But it has no impact on the results.

The DISTINCT keyword can be very useful when used with other contexts (e.g. with the COUNT() function), but it has no meaning when used with MIN(). The DISTINCT keyword removes duplicates, but in the case of MIN() it won’t make any difference because MIN() returns the same result regardless of how many rows share the same minimum value.

Window Functions

The MIN() function can be used in conjunction with the OVER clause to create a window function.

See SQL MIN() For Beginners for an example.