Update all date columns in SQL Server -1 day

Question

I want to update my database (SQL Server Express) all the dates for specific ids.

I am displaying the ids I want to.

SELECT TOP (1000) ID, Dates
FROM tbl_table
WHERE (id IN (29695, 29700, 29701, 29702, 29703, 29704, 29705, 29706, 29707, 29708, 29709, 29710, 29711, 29712, 29713, 29714, 29715))

AND my dates in the database are like this:

Is there any way to update all the date columns with same date - 1 day?

For example: if we have 2019-12-20, update it to 2019-12-19?

For example if I want to do it in PHP, I would loop through this query and fetch all all dates. After I would remove one day like this:

date('m/d/Y', strtotime($date. ' - 1 days');

And create a query to update all the columns based on id. I just want to avoid that. Is there any SQL command that do that?

Thanks

Answer 1

The request below will update the rows you want by adding -1 days on each date:

UPDATE tbl_table 
SET    dates = Dateadd(day, -1, dates) 
WHERE  id IN ( 29695, 29700, 29701, 29702, 
               29703, 29704, 29705, 29706, 
               29707, 29708, 29709, 29710, 
               29711, 29712, 29713, 29714, 29715 )

DATEADD function takes 3 parameters:

1. the interval ( day, month, year ..)
2. the increment (the value to add or remove if negative)
3. an expression (wich is a datetime type)

See DATEADD documentation