declare
type v_arr is table of varchar2(40) index by binary_integer;
list v_arr;
existing_table number;
v_sql varchar2(200);
begin
existing_table := 0;
list(1) := 'table1';
list(2) := 'table2';
for i in 1..list.count loop
select count(*) into existing_table from all_tables where table_name=list(i) and owner='root';
if existing_table = 1 then
v_sql := 'drop table '||list(i);
execute immediate v_sql;
end if;
end loop;
commit;
end;