Question

How do I add time to a datetime field with an indexing value?

My RDBMS is SQL Server 2008 R2.

I want to start at noon for a datetime field and for every record, take the base value of noon and add 15 seconds and set it for the record.

Example

Record 1: DateTime Value = '12:00:00 pm'
Record 2: DateTime Value = '12:00:15 pm'
Record 3: DateTime Value = '12:00:30 pm'
...n...

I toyed with a UPDATE query, but I couldn’t get it to index. I’m feeling this might require a function, but I’m not sure.

Ideas?

Respectfully,

Ray

Answer 1

Assuming that you have a table YourTable with a datetime column Value that you need to fill with a datetime value incremented by 15 seconds for each row. Here I use a column ID to specify the order of the rows.

declare @Start datetime = '2011-05-18T12:00:00'

;with cte as
(
  select Value,
    row_number() over(order by ID) as rn
  from YourTable 
)
update cte set
  Value = dateadd(s, 15*(rn-1), @Start)