After insert & update trigger

Question

I need to write a trigger that if some columns of the master table have changed, the trigger will first insert the change to a copy table. Later on, if there are more changes to the master of the same row, it will compare the new value to the old value and delete the same row in the copy table and insert the latest change. I have wrote the following trigger. Some how when I run it, it has compilation error. Does anyone have any idea on how should I approach this?
create or replace trigger TRITON.AFTER_INSERT_UPDATE_ITM001100after insert or update on TRITON.TTIITM001100for each rowdeclarev_reflag char(1);beginv_reflag:='0';if (:new.T$ITEM != :old.T$ITEM or :new.T$DSCA != :old.T$DSCA) then
delete from ticcrm.ttiitm001100_copy;
insert /*+append*/ into ticcrm.ttiitm001100_copy(T$ITEM, T$DSCA, T$DSCB, T$DSCC, T$DSCD, T$WGHT, T$SEAK, REFLAG)values(:new.T$ITEM, :new.T$DSCA, :new.T$DSCB, :new.T$DSCC, :new.T$DSCD, :new.T$WGHT, :new.T$SEAK, v_reflag);
end if;
end;
/

Answer 1

delete from ticcrm.ttiitm001100_copy;
insert /*+append*/ into ticcrm.ttiitm001100_copy(T$ITEM, T$DSCA, T$DSCB, T$DSCC, T$DSCD, T$WGHT, T$SEAK, REFLAG)values(:new.T$ITEM, :new.T$DSCA, :new.T$DSCB, :new.T$DSCC, :new.T$DSCD, :new.T$WGHT, :new.T$SEAK, v_reflag);
This is simple SQL statements, not PL/SQL.
Use EXECUTE IMMEDIATE for executing it.
P.S. Please do not forget to make good formatting of your code before posting it.