There are several applications for customized function strings.
Perform operations in any native database language (including those other than Transact-SQL) by altering function-string output templates to format the commands sent to a data server.
Materialize and dematerialize multiple subscriptions for the same replication definition with a single function string.
Record auditing information.
Execute remote procedure calls (RPCs).
Replicate data into multiple replicate tables in the same database.
Replicate data into a replicate table with a different name, column names, or column order than the primary table.
If the replicate Replication Server is version 11.5 or later, you can perform the same tasks more easily by creating a customized replication definition that specifies the relevant information about the replicate table. See Replication Server Administration Guide Volume 1 > Manage Replicated Tables > Create Replication Definitions > Create Multiple Replication Definitions Per Table.