Filtering Published Data

Horizontal, vertical, dynamic, and join filters enable you to create partitions of data to be published. By filtering published data, you can:

• Minimize the amount of data sent over the network.
  
  
• Reduce the amount of storage space required at the Subscriber.
  
  
• Customize publications and applications based on individual Subscriber requirements.
  
  
• Avoid or reduce conflicts because the different data partitions can be sent to different Subscribers (no two Subscribers will be updating the same data values).

Row and column filters can be used with snapshot, transactional, and merge publications. Row filters use the WHERE clause of an SQL statement and restrict the rows included in a publication based on specific criteria. Column filters restrict the columns that are included in a publication.

Dynamic and join filters extend the capabilities of merge replication. Dynamic filters are row filters that use a function to retrieve a value from the Subscriber and filter data based on that value. The filter is defined once for a publication, but the qualifying result set can be different for each Subscriber and allows the user at a Subscriber to receive only the subset of data customized for their needs.

Join filters extend a row filter from one published table to another. A join filter defines a relationship between two tables that will be enforced during the merge process; it is similar to specifying a join between two tables.