SQL Server Date Add for Dev: A Beginner’s Guide

Greetings Dev! Are you struggling with SQL Server Date Add? Look no further! This article will guide you through the basics of SQL Server Date Add and help you to become a pro in no time. Let’s dive in!

What is SQL Server Date Add?

SQL Server Date Add is a function used to add or subtract a specified interval from a date. This function is useful in many applications, especially for financial calculations, scheduling, and data analysis. The syntax for SQL Server Date Add is as follows:

Argument	Data Type	Description
Datepart	varchar	The part of the date to be added or subtracted
Number	int	The number of intervals to be added or subtracted
Date	datetime	The starting date

Let’s discuss each argument in detail.

Datepart

Datepart specifies the part of the date that should be added or subtracted. Here are the supported values for Datepart:

Value	Description
year	Adds or subtracts a year
quarter	Adds or subtracts a quarter
month	Adds or subtracts a month
dayofyear	Adds or subtracts a day of the year
day	Adds or subtracts a day
week	Adds or subtracts a week
weekday	Adds or subtracts a weekday
hour	Adds or subtracts an hour
minute	Adds or subtracts a minute
second	Adds or subtracts a second
millisecond	Adds or subtracts a millisecond

Number

The Number argument specifies the number of intervals to be added or subtracted. This argument can be negative or positive. For example, if you want to add 5 days to a given date, the number argument would be 5. If you want to subtract 2 months from a given date, the number argument would be -2.

Date

The Date argument specifies the starting date. This argument must be a valid datetime data type. If the Date argument is null, the function will return null.

How to Use SQL Server Date Add?

Step 1: Create a Sample Table

Before we dive into the usage of SQL Server Date Add, let’s create a sample table for our example queries:

“`CREATE TABLE SampleTable (ID INT PRIMARY KEY,StartDate DATETIME);INSERT INTO SampleTable (ID, StartDate)VALUES (1, ‘2022-10-01’), (2, ‘2022-11-01’), (3, ‘2022-12-01’);“`

Step 2: Add Days to a Date

Let’s add 5 days to the StartDate column in the SampleTable:

“`SELECT ID, DATEADD(day, 5, StartDate) AS EndDateFROM SampleTable;“`

This query will return a new column called EndDate, where the StartDate column is incremented by 5 days. The result will be:

ID	EndDate
1	2022-10-06 00:00:00.000
2	2022-11-06 00:00:00.000
3	2022-12-06 00:00:00.000

Step 3: Subtract Months from a Date

Let’s subtract 2 months from the StartDate column in the SampleTable:

“`SELECT ID, DATEADD(month, -2, StartDate) AS NewDateFROM SampleTable;“`

This query will return a new column called NewDate, where the StartDate column is decremented by 2 months. The result will be:

ID	NewDate
1	2022-08-01 00:00:00.000
2	2022-09-01 00:00:00.000
3	2022-10-01 00:00:00.000

FAQs

What happens if the starting date is null?

If the Date argument in SQL Server Date Add is null, the function will return null.

What happens if the number argument is negative?

If the Number argument in SQL Server Date Add is negative, the function will subtract the specified interval from the starting date.

What is the maximum value for the Number argument?

The maximum value for the Number argument in SQL Server Date Add is 2,147,483,647.

Can I add fractions of an interval?

No, the Number argument in SQL Server Date Add only accepts whole numbers.

What data type does SQL Server Date Add return?

SQL Server Date Add returns a datetime data type.

Conclusion

Congratulations Dev, you’ve successfully learned the basics of SQL Server Date Add! You can now add or subtract intervals from a date with ease. Remember to use this function to simplify your financial calculations, scheduling, and data analysis. Keep practicing and you’ll be a pro in no time!