Introduction to PostgreSQL real Data Type

The real data type in PostgreSQL is a floating-point type that can store single-precision floating-point numbers (32 bits).

Syntax

The syntax for defining a real data type is as follows:

column_name real

Use Cases

The real data type is commonly used for storing numeric values with decimal parts, such as temperature, velocity, price, etc. It is widely used in fields like science, engineering, finance, etc.

Compared to the double precision data type, the real data type uses less storage space but has slightly lower precision. If you need higher precision, you can use the double precision data type.

Examples

Here are two examples of using the real data type:

Example 1

In this example, we will create a table named temperature with a real column named value to store temperature values.

CREATE TABLE temperature (
    id SERIAL PRIMARY KEY,
    value REAL
);

INSERT INTO temperature (value) VALUES (24.5);
INSERT INTO temperature (value) VALUES (26.8);

Now, we can query the temperature table and calculate the average value of all temperature values:

SELECT AVG(value) FROM temperature;

The result is:

 avg
--------
 25.65
(1 row)

Example 2

In this example, we will create a table named product with a real column named price to store product prices.

CREATE TABLE product (
    id SERIAL PRIMARY KEY,
    name VARCHAR(50),
    price REAL
);

INSERT INTO product (name, price) VALUES ('Product A', 19.99);
INSERT INTO product (name, price) VALUES ('Product B', 29.99);

Now, we can query the product table and calculate the sum of all product prices:

SELECT SUM(price) FROM product;