Oracle - Convert varchar2 to Clob datatype

In order to convert a column datatype from varchar2 to clob do:

step 1 - add a column with clob datatype:

_alter table add( clob);


step 2 - copy data from the source column to the new one:

_update set \= ;


step 3 - rename the new column created in the step 1 in order to complete the process:

_alter tablerename column_ to _;
alter table
rename column_ to ;