Technique for changing a clob to varchar2 in Oracle without dropping/recreating table or altering column positions.

Convert Oracle clob to varchar2

alter table t add c2 varchar2(4000);
update t set c2 = c;
update t set c = null;
commit;
alter table t modify c long;
alter table t modify c clob;
update t set c = c2;
alter table t drop column c2;
commit;