SQL Server DATEADD Function to Add or Subtract Dates

DATEADD (datepart, number, date)

In this function

1^st Argument “datepart” is the interval type we need to add or subtract for example day, month, year, hour, minute, second.

Datepart can be one of the following:

2^nd Argument the number is the amount of datepart units to add or subtract. For example if datepart was d and the number was 3 then it would add three days to the date specified.

3^rd Argument date is the date to add/subtract the number of dateparts from. It can either be a column in the database, a constant value or a function such as GETDATE() which would return the current date and time.

Suppose if we want to add one month to present date we need to write the query like this

Output:

Suppose if we want to subtract one month from present date we need to write the query like this

Output:

We have Orders table like this

Now I need to add 15 days to “OrderDate” for that we need to write the query like this

Output:

This way we can use DATEADD function to add or subtract dates from specified time interval in SQL