- Aggregate functions
- ALTER TABLE statement
- AVERAGE function
- BETWEEN operator
- CASE expression
- CAST() function
- COALESCE() function
- Comment
- Common table expression
- CONCAT() function
- Constraints
- CONTAINS
- CONVERT function
- COUNT() function
- CREATE TABLE statement
- CROSS JOIN
- Cursor
- Data types
- Date functions
- DATEADD() function
- DATEDIFF() function
- DELETE statement
- DROP TABLE statement
- EXISTS operator
- FORMAT() function
- GROUP BY statement
- HAVING clause
- IF statement
- Index
- Injection
- INNER JOIN
- INSERT INTO statement
- IS NOT NULL condition
- IS NULL condition
- Joins
- LAG function
- LEFT JOIN
- LENGTH() function
- LIKE operator
- LIMIT clause
- MERGE statement
- Normalization
- Not equal
- Operators
- ORDER BY clause
- Partition
- Pivot table
- Regex
- REPLACE function
- ROUND function
- SELECT DISTINCT clause
- SELECT statement
- Set operators
- Stored procedure
- String functions
- Subquery
- Substring
- Temporary table
- Transaction
- Trigger
- TRUNCATE TABLE
- UPDATE statement
- Views
- WHERE clause
- Window functions
SQL
SQL DATEADD() Function: Syntax, Usage, and Examples
The SQL DATEADD
function lets you add or subtract a specified time interval from a date. It’s commonly used for scheduling, setting future deadlines, or shifting timestamps for reporting. DATEADD SQL
is primarily supported in SQL Server and Transact-SQL environments.
How to Use DATEADD in SQL
The general syntax for SQL DATEADD
is:
DATEADD(datepart, number, date)
datepart
: The unit of time to add (e.g., year, month, day, hour)number
: The number of units to add (can be negative to subtract)date
: The base date to modify
Basic Example
SELECT DATEADD(day, 7, '2023-05-01') AS new_date;
-- Output: 2023-05-08
This query adds 7 days to May 1, 2023.
When to Use DATEADD SQL
The sql dateadd
function is useful anytime you need to shift a date or time value programmatically. Use cases include:
- Calculating expiration or renewal dates
- Forecasting future tasks or deadlines
- Subtracting days from current timestamps
- Creating rolling time windows in reports
- Automating recurring event dates
Real-Life Scenarios
Setting Subscription End Dates
SELECT user_id, DATEADD(month, 1, start_date) AS renewal_date
FROM subscriptions;
Adds one month to each user's start date.
Creating a Reporting Window
SELECT *
FROM orders
WHERE order_date >= DATEADD(day, -30, GETDATE());
Filters orders placed in the last 30 days.
Examples of SQL DATEADD
Example 1: Adding Days to a Date
SELECT DATEADD(day, 10, '2023-06-01') AS future_date;
-- Output: 2023-06-11
A straightforward use of dateadd function in sql
to move 10 days ahead.
Example 2: Subtracting Time
SELECT DATEADD(day, -15, GETDATE()) AS fifteen_days_ago;
Use a negative number to go back in time.
Example 3: SQL DATEADD with Other Units
SELECT
DATEADD(year, 1, hire_date) AS one_year_later,
DATEADD(month, 6, hire_date) AS half_year_later,
DATEADD(week, 2, hire_date) AS in_two_weeks
FROM employees;
This highlights how flexible sql dateadd function
can be with multiple time units.
Learn More About DATEADD SQL
Common Datepart Values
In dateadd sql server
, these datepart
values are supported:
year
,yy
,yyyy
quarter
,qq
,q
month
,mm
,m
day
,dd
,d
week
,wk
,ww
hour
,hh
minute
,mi
,n
second
,ss
,s
millisecond
,ms
Example:
SELECT DATEADD(minute, 30, '2023-01-01 10:00:00') AS new_time;
-- Output: 2023-01-01 10:30:00
Combining DATEADD with DATEDIFF
You can combine SQL DATEADD
with DATEDIFF
to round or normalize dates.
Round a date down to the start of the month:
SELECT DATEADD(month, DATEDIFF(month, 0, GETDATE()), 0) AS month_start;
This is a popular trick in analytics or calendar-based reporting.
SQL Query DATEADD with GETDATE()
In SQL Server and Transact-SQL systems, GETDATE()
returns the current timestamp. You can use it in sql query dateadd
to create rolling intervals:
SELECT DATEADD(hour, -12, GETDATE()) AS twelve_hours_ago;
This is useful for building time-sensitive dashboards.
Transact SQL DATEADD in Conditional Logic
Use transact sql dateadd
in a CASE
statement:
SELECT
user_id,
subscription_type,
DATEADD(day,
CASE
WHEN subscription_type = 'trial' THEN 14
WHEN subscription_type = 'monthly' THEN 30
WHEN subscription_type = 'annual' THEN 365
END,
signup_date
) AS expiration_date
FROM users;
This calculates different expiration dates based on subscription plans.
Adjusting Dates for Business Logic
If you need to calculate due dates while skipping weekends or holidays, combine DATEADD
with business rules or helper tables.
-- Add 1 day, then skip to Monday if it’s Saturday or Sunday
SELECT
CASE
WHEN DATENAME(weekday, DATEADD(day, 1, GETDATE())) IN ('Saturday', 'Sunday')
THEN DATEADD(day, 3, GETDATE()) -- Adjust to Monday
ELSE DATEADD(day, 1, GETDATE())
END AS adjusted_due_date;
This is useful in logistics, HR, and invoicing workflows.
Using DATEADD for Partitioning and Reporting
You can dynamically create time buckets using sql dateadd function
:
SELECT
customer_id,
COUNT(*) AS orders_last_90_days
FROM orders
WHERE order_date >= DATEADD(day, -90, GETDATE())
GROUP BY customer_id;
This is a standard approach in behavioral analysis and churn prediction.
DATEADD SQL Server Specific Behavior
In dateadd sql server
, if your base date is of datetime
type, DATEADD
retains fractional seconds and time zone context.
SQL Server also supports fractional units:
SELECT DATEADD(second, 1.5, '2023-06-01 12:00:00') AS precise_time;
-- Output: 2023-06-01 12:00:01.500
You can use this for more granular log or event tracking.
Avoiding Common Pitfalls
- Overflow Errors: Adding large values like 10000 years can cause overflow.
- Mismatched Types: If the
date
input isn't properly typed, you may need to useCAST()
:
SELECT DATEADD(day, 7, CAST('2023-06-01' AS DATE));
- Invalid Datepart Strings: Misspelled or unsupported
datepart
values will trigger errors. Always check the docs.
Using DATEADD in Views and CTEs
DATEADD SQL
can also be used in common table expressions (CTEs) and views:
WITH recent_activity AS (
SELECT user_id, last_login
FROM users
WHERE last_login >= DATEADD(day, -30, GETDATE())
)
SELECT * FROM recent_activity;
This keeps logic reusable across reporting and application layers.
The SQL DATEADD
function is a powerful and flexible tool for managing time in your databases. Whether you're forecasting deadlines, filtering recent activity, or calculating future schedules, DATEADD SQL
provides clean, efficient solutions. By combining it with functions like GETDATE()
, DATEDIFF
, and CASE
, you can build robust temporal logic into your reports, business rules, and applications. Once you’ve mastered dateadd sql server
usage patterns and edge cases, you’ll be able to confidently handle even the most complex time-based calculations in your SQL workflows.
Sign up or download Mimo from the App Store or Google Play to enhance your programming skills and prepare for a career in tech.