[Column name] nicknames [Data type] varbinary(1001) [Description] 
A list of nicknames of other Subscribers that are known to already have this generation. It is used to avoid sending a generation to a Subscriber that has already seen those changes. Nicknames in the nicknames list are maintained in sorted order to make searches more efficient. If there are more nicknames than can fit in this field, they will not benefit from this optimization.