The Language Implementation
------------------------------------------------------------------------------

     To support the RDD architecture and let you design applications that are
     independent of the data format you are using, many existing CA-Clipper
     commands and functions have been enhanced, and several new language
     elements have been added.  The following tables summarize these changes
     and additions.  See the Reference chapter of this guide for more
     detailed information on a particular item.

     Enhanced Commands and Functions
     ------------------------------------------------------------------------
     Command/Function  Changes
     ------------------------------------------------------------------------
     APPEND FROM       VIA clause
     COPY TO           VIA clause
     DBAPPEND()        Terminology
     GO                Terminology
     DBAPPEND()        Terminology
     INDEX             ALL, EVAL, EVERY, NEXT, RECORD, REST, TAG, and
                       UNIQUE clauses
     SEEK              SOFTSEEK option
     SET INDEX         ADDITIVE clause
     SET ORDER         IN, TAG clauses
     DBSETINDEX()      Terminology
     RECNO()           Terminology
     ------------------------------------------------------------------------

     New Commands and Functions
     ------------------------------------------------------------------------
     Command/Function    Description
     ------------------------------------------------------------------------
     DELETE TAG          Delete a Tag (Order)
     DBGOTO()            Position record pointer to a specific identity
     DBRLOCK()           Lock the record at the current or specified identity
     DBRLOCKLIST()       Return an array of the currently locked records
     DBRUNLOCK           Release all or specified record locks
     ORDBAGEXT()         Return the Order Bag file extension
     ORDBAGNAME()        Return the Order Bag name of a specific Order
     ORDCREATE()         Create an Order in an Order Bag
     ORDDESTROY()        Remove a specified Order from an Order Bag
     ORDFOR()            Return the FOR expression of an Order
     ORDKEY()            Return the Key expression of an Order
     ORDLISTADD()        Add Order Bag contents or single Order to the Order
                         List
     ORDLISTCLEAR()      Clear the current Order List
     ORDLISTREBUILD()    Rebuild all Orders in the Order List of the current
                         work area
     ORDNAME()           Return the name of an Order in the work area
     ORDNUMBER()         Return the position of an Order in the current Order
                         List
     ORDSETFOCUS()       Set focus to an Order in an Order List
     RDDLIST()           Return an array of the available Replaceable
                         Database Drivers
     RDDNAME()           Return the name of the RDD active in the current or
                         specified work area
     RDDSETDEFAULT()     Set or return the default RDD for the application
     ------------------------------------------------------------------------