Question

i have a table where i want to track time so a valid entry might be:

• 1 hour 3 mins
• 47 mins
• 10 hours
• 3 mins 14 seconds

what field type is best used for this. i obviously could use varchar . .but i thought there might be something better as i would like to run queries to total the amount of time over a number of records.

Answer 1

Do not use character types to store date/time information.

In SQL Server 2008, you have the time type for this, which is what you should use if your time intervals are less than 1 day. In previous versions, or if you need to store larger intervals, you will have to use datetime or smalldatetime (depending on the precision you need).

Another option would be to choose a time unit – say, minutes – and just use an int value to represent the number of units. Just make sure that (a) the unit you choose is actually precise enough to record the smallest intervals you need to track, and (b) the actual numeric type is large enough to hold the largest intervals you need to track. A smallint might be sufficient for tracking the number of minutes within a day; on the other hand, tracking the number of milliseconds within a 10-year timeframe would have to be stored as a bigint.