text: --+ holdcas on;
  --alter_table_change_type_strict
  --change the type of a nchar() column to double
  
  create class coo(
          col1 nchar(50),
          col2 nchar(50),
          col3 nchar(50),
          col4 nchar(50),
  	col5 nchar(50),
  	col6 nchar(50),
  	col7 nchar(50),
  	col8 nchar(100)
  );
  
  insert into coo
   values(n'-823342341234127.923123', n'1.7976931348623157E+308', n'1.7976931348623157E+310', n'-1.7976931348623157E+308', n'-1.7976931348623157E+309', n'234234523452345223.90728102893401982374883740192', n'abc', n'lsakdjfjjdkjsldfjkdkdksllaieywieuriwue78236423746iuyuisjkfhskdjfhwkehkwehfkwefhw');
  
  
  show columns in coo;
  select * from coo order by 1;
  
  
  --nchar() -> double, number format -> number, no loss of data
  alter table coo change col1 col1 double;
  select col1 from coo order by 1;
  
  --nchar() -> double, number format -> number, nchar() = max(double)
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col2 col2 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col2 col2 double;
  select col2 from coo order by 1;
  
  --nchar() -> double, number format -> number, nchar() > max(double)
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col3 col3 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col3 col3 double;
  select col3 from coo order by 1;
  
  --nchar() -> double, number format -> number, nchar() = min(double)
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col4 col4 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col4 col4 double;
  select col4 from coo order by 1;
  
  --nchar() -> double, number format -> number, nchar() < min(double)
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col5 col5 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col5 col5 double;
  select col5 from coo order by 1;
  
  --nchar() -> double, number format -> number, loss of data
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col6 col6 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col6 col6 double;
  select col6 from coo order by 1;
  
  
  --nchar() -> double, string -> number, no loss of data
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col7 col7 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col7 col7 double;
  select col7 from coo order by 1;
  
  
  --nchar() -> double, long string -> number, loss of data
  set system parameters 'alter_table_change_type_strict=yes';
  alter table coo change col8 col8 double;
  set system parameters 'alter_table_change_type_strict=no';
  alter table coo change col8 col8 double;
  select col8 from coo order by 1;
  
  
  
  show columns in coo;
  
  drop table coo;
  
  
  commit;
  --+ holdcas off;
  