# What are the SQL Aggregate Functions? Complete Guide

In this article, we are going to discuss SQL Aggregate Functions using practical examples with syntax.

## List Of Aggregate Functions

Below are the commonly used SQL Aggregate Functions.

1. AVG – Returns the average value for the selected column in the table
2. COUNT – Returns the number of rows for the selected column in the table
3. FIRST – Returns the first value for the selected column in the table
4. LAST – Returns the last value for the selected column in the table
5. MAX – Returns the largest value for the selected column in the table
6. MIN – Returns the smallest value for the selected column in the table
7. SUM – Returns the sum value for the selected column in the table.

Now I am going to use the Employee table to work on these aggregate functions.

### AVG() Function

Average returns average value of a numeric column

The Syntax for this function is as follows

```SELECT AVG(column_name)
FROM table_name```

### Practical Use Of AVG Function

Consider the following Employee Table

SQL Query to find Average Salary as Follows

```Select AVG(Salary)
From Employee;```

Result of the above query will be as follows.

### Count() Function

Here count returns the number of rows present in the employee table either based on some condition or without condition.

The syntax for this function is as follows.

```SELECT Count(column_name)
FROM table_name```

### Practical Use Of Count Function

Consider the following Employee Table.

SQL query to count number of employee based on certain condition is as follows.

```SELECT COUNT(Name) FROM Employee
WHERE Salary = 6000.25;```

Result of the above query will be

### FIRST() Function

First function returns first value of a selected column in the table.

Syntax for FIRST function is as follows

```SELECT FIRST(column_name)
FROM table_name;```

### Practical Use Of FIRST Function

Consider the following employee table

SQL query for this function will be as follows

```SELECT FIRST(Salary)
FROM Employee```

and the results will be as follows

### LAST() Function

Last function returns the last value of the selected column in the table.

Syntax for the last function is as follows

Consider the following employee table

SQL Query for this function is as follows

```SELECT LAST(Salary)
FROM Employee```

Result of the above query will be as follows.

### MAX() Function

Max function returns the maximum value of the selected column for a particular table.

Syntax for this function is as follows,

```SELECT MAX(column_name)
FROM table_name;```

Practical use of MAX function is as follows

Consider the following employee table for this function

SQL query to find the maximum salary from the table is as follows.

```SELECT MAX(Salary)
FROM Employee```

Result of the query will be as follows.

### MIN() Function

Minimum function returns the minimum value of the selected column in the specific table

Syntax for MIN function is as follows

```SELECT MIN(column_name)
FROM table_name ```

Practical use of MIN Function

Consider the following employee table

SQL query to find the minimum salary from the employee table is as follows

```SELECT MIN(Salary)
FROM Employee```

Results for this query will be as follows

### SUM() Function

SUM function returns the total sum of selected column for a particular table.

Syntax for this function is as follows

```SELECT SUM(table_name)
FROM column_name```

### Practical use of SUM function is as follows

Let us consider the following employee table

SQL query to find the SUM of salary from employee table is as follows.

```SELECT SUM(Salary)
FROM Employee;```

Results for the query will be as follows