text: ---- ALTER TABLE ...  CHANGE COLUMN  
  -- constraints : DEFAULT
  -- ordering : no order defined
  -- name : same of different
  -- type : change
  -- other :
  
  
  
  --  check update of 'DEFAULT' original value    - column is added with alter
  create table t1 ( i1 integer );
  
  insert into t1 set i1 = 0;
  
  alter table t1 add column d1 date default date'1999-09-09';
  
  insert into t1 values (1,date'2001-01-01');
  insert into t1 set i1 = 2;
  select * from t1 order by 1,2;
  show columns in t1;
  
  -- change to datetime, drop default
  alter table t1 change d1 dt1 datetime;
  
  insert into t1 set i1 = 3;
  insert into t1 values (4,datetime'2004-04-04 04:04:04');
  show columns in t1;
  select * from t1 order by 1,2;
  
  
  -- add the default again
  alter table t1 change dt1 dt1 datetime default datetime'1999-09-09 09:09:09';
  insert into t1 set i1 = 7;
  insert into t1 values (8,datetime'1888-08-08 08:08:08');
  
  show columns in t1;
  select * from t1 order by 1,2;
  
  drop table t1;
  
  
  
  