Hello ,
In session when we defines synchronized child sessions in main session, it will open child session as detail view of main session and main table for both child and parents sessions are same,then how to open child session with different main table as synchronized child?. It is possible with mmt session and by adding form command.but w/o this 2 method how it is possible?

Did you try with - start.synchronized.child() (http://www.baanboard.com/programmers_manual_baanerp_help_functions_synchronized_sessions_start_synchronized_child)

Use this to synchronize two sessions that act on different main tables. The function starts the specified child session when the user chooses a particular form command in the multioccurrence parent session. The primary key of the parent's main table must be a subset of the primary key of the child's main table.

Although you normally use this function to synchronize sessions that act on different main tables, it is also possible to use it to synchronize sessions that act on the same main table.