Vertical filtering alters the construction of the column list for a snapshot or transactional publication (vertical filtering is not supported for merge publications). This feature does not pose a significant effect on performance and, in some cases, reduces the amount of time it takes to apply replicated changes at the Subscriber. Microsoft® SQL Server™ does not currently support vertical filtering for merge publications. You can achieve similar results, however, by creating two tables that have a one-to-one ordinality and publishing only the one with the columns of interest.
Vertical filtering can be used to limit the columns replicated as part of an article. It can decrease the volume of data traffic across the network or the size of site storage by eliminating large text or image columns that may be unnecessary for certain Subscribers. The following diagram illustrates vertical filtering.
You can also use both horizontal and vertical filtering together, as illustrated in the following diagram.
