Ok so say I have 100 rows to insert and each row has about 150 columns (I know that sounds like a lot of columns, but I need to store this data in a single table). The inserts will occur at random, (ie whenever a set of users decide to upload a file containing the data), about a 20 times a month. However the database will be under continuous load processing other functions of a large enterprise application. The columns are varchars, ints, as well as a variety of other types.
Is the performance gain of wrapping these inserts in a transaction (as opposed to running them one at a time) going to be huge, minimal, or somewhere in between?
Why?
EDIT: This is for Sql Server 2005, but I'd be interested in 2000/2008 if there is something different to be said. Also I should mention that I understand the point about transactions being primarily for data-consistency, but I want to focus on performance effects.