# Aggregate Functions

## **COUNT** 

The COUNT function returns the number of rows in a group. It counts all values including NULL values.

```sql
SELECT COUNT(column_name) FROM table_name; 
```

## **SUM**

The SUM function returns the total sum of values in a numeric column. It ignores NULL values.

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

## **AVG** 

The AVG function returns the average value of a numeric column. It ignores NULL values.

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

## **MAX**

The MAX function returns the maximum value in a set of values. It ignores NULL values.

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

## **MIN** 

The MIN function returns the minimum value in a set of values. It ignores NULL values.

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

## **FIRST** 

The FIRST function returns the first value in a set of values. It ignores NULL values.

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

## **LAST** 

The LAST function returns the last value in a set of values. It ignores NULL values.

```sql
SELECT LAST(column_name) FROM table_name;
```


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