What Is Float8 Data Type?

The float8 data type is a numeric data type in PostgreSQL that represents floating-point numbers with precision up to 15 decimal places. It is also known as the double precision data type. Float8 data type can store both positive and negative numbers with a wide range of values.

## Features of Float8 Data Type

**Precision:**Float8 data type offers a higher level of precision compared to the float4 (single precision) data type.**Range:**The range of values that can be stored in float8 is approximately -1.79E+308 to 1.79E+308.**Storage Size:**The storage size of the float8 data type is 8 bytes.**Arithmetic Operations:**Float8 supports various arithmetic operations such as addition, subtraction, multiplication, and division.

## Usage Examples

To better understand the usage of the float8 data type, let’s consider a few examples:

### Addition

To add two float8 numbers, you can simply use the ‘+’ operator as shown below:

```
SELECT 12.34::float8 + 56.78::float8;
```

In this example, the result will be 69.12.

### Multiplication

If you want to multiply two float8 numbers, you can use the ‘*’ operator like this:

```
SELECT 2.5::float8 * 7::float8;
```

The result of this multiplication will be 17.5.

### Comparison

Float8 data type also allows comparison operations. For example, you can compare two float8 numbers using the ‘<' operator:

```
SELECT 10::float8 < 15::float8;
```

In this case, the result will be true (or 't' in PostgreSQL).

## Conclusion

The float8 data type in PostgreSQL provides a higher level of precision for storing floating-point numbers. It offers a wider range of values and supports various arithmetic operations and comparisons. Understanding the features and usage examples of the float8 data type can greatly assist in working with numeric values in PostgreSQL databases.