SQL DATEADD() Function

SQL DATEADD()

The SQL DATEADD() function is used to add a specific time interval to a date value. This function is commonly used to manipulate dates by adding days, months, years, hours, or other time units.

In this tutorial, we will explore the DATEADD function, its syntax, and how to use it effectively with practical examples.

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Syntax of SQL DATEADD Function

The syntax of the DATEADD function is as follows:

DATEADD(interval, number, date_value)

Parameters:

• interval: The unit of time to add (e.g., year, month, day, hour, minute).
• number: The number of intervals to add to the date.
• date_value: The starting date to which the interval is added.

Common Interval Values:

Interval	Description
year	Year
month	Month
day	Day
hour	Hour
minute	Minute
second	Second

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Step-by-Step Examples Using SQL DATEADD

1 Adding Days to a Date

Let’s assume we have a table named employees that stores employee details, including their joining date.

We create the table in Microsoft SQL Server:

CREATE TABLE employees (
    id INT PRIMARY KEY IDENTITY(1,1),
    name VARCHAR(50),
    joining_date DATE
);

Insert some sample data:

INSERT INTO employees (name, joining_date)
VALUES 
('Arjun', '2023-01-15'),
('Ram', '2022-11-20'),
('Priya', '2023-05-10');

Now, let’s use the DATEADD function to calculate the review date by adding 180 days to each employee’s joining date:

SELECT name, joining_date, DATEADD(day, 180, joining_date) AS review_date
FROM employees;