In a multiple database environment, there is always the possibility of two users updating the same record simultaneously on two different databases. When creating a replicated system, consider designing the system to avoid or at least minimize collisions.

To reduce collisions significantly or eliminate them altogether, design transactions that allow newly created information to be presented in the form of inserts and deletes instead of updates. This is particularly true for updates to key columns.

For information on how to resolve collisions, see Collision Resolution.