The following example shows how to erase all the yachts built by
       Albin:

       DTR> FIND YACHTS WITH BUILDER EQ "ALBIN"
       [3 records found]
       DTR> ERASE ALL

       In the following example, a procedure is defined that erases
       selected yachts:

       DTR> DEFINE PROCEDURE SELL_BOAT
       DFN>     FIND YACHTS WITH BUILDER EQ *.BUILDER AND
       DFN>          MODEL = *.MODEL
       DFN>     PRINT ALL
       DFN>     IF *."Y IF BOAT SOLD" CONT "Y" THEN ERASE ALL
       DFN> END_PROCEDURE
       DTR>