When you mark a stored procedure for replication, Mirror Replication Agent creates a shadow-row procedure for that stored procedure.
Mirror Replication Agent also modifies the marked stored procedure as follows:
Inserts a new first step to execute the associated shadow-row procedure
Inserts a new last step to again execute the shadow-row procedure with different parameters.
When you unmark an object that has been marked for replication, the transaction log objects that were created to facilitate the replication for that object are removed from the primary database.
When you mark a stored procedure for replication, Mirror Replication Agent creates the transaction log objects that capture the stored procedure invocation in the transaction log.
DDL replication must be disabled during the marking
of stored procedures. Because marking of a stored procedure modifies
that stored procedure, you must first disable DDL replication to
prevent the marking modifications from replicating to the standby
site.
