SQL - Date & Time Functions in SQL

Date & Time functions are used to work with dates and timestamps in SQL. They help in calculations, formatting, and comparing date values. These functions are widely used in attendance systems, billing, reporting, and analytics.

Common Date & Time Functions

Function

Description

Example

NOW()

Returns current date & time

NOW()

CURDATE()

Returns current date

CURDATE()

CURTIME()

Returns current time

CURTIME()

DATE()

Extracts date from datetime

DATE(order_time)

DATEDIFF(date1, date2)

Difference between two dates

DATEDIFF('2025-12-10','2025-12-01')

DATE_ADD()

Adds days/months/years

DATE_ADD(date, INTERVAL 5 DAY)

DATE_SUB()

Subtracts days/months/years

DATE_SUB(date, INTERVAL 2 MONTH)

YEAR()

Extracts year from date

YEAR(order_date)

MONTH()

Extracts month from date

MONTH(order_date)

DAY()

Extracts day from date

DAY(order_date)


Example Table

CREATE TABLE orders (

  id INT,

  customer_name VARCHAR(50),

  order_date DATE

);

INSERT INTO orders VALUES

(1, 'Ashika', '2025-12-01'),

(2, 'Rohan', '2025-11-20');

Example Queries

1. Get today’s date:

SELECT CURDATE();

2. Find how many days ago order was placed:

SELECT customer_name, DATEDIFF(CURDATE(), order_date) AS days_ago

FROM orders;

3. Add 7 days to order date:

SELECT customer_name, DATE_ADD(order_date, INTERVAL 7 DAY) AS delivery_date

FROM orders;

Key Points

  • Used for calculating ages, deadlines, and durations
  • Works with DATE, TIME, and DATETIME data types
  • Very important in real-time applications