CLOB data type

Question

Problem in firing 'IF' statement which is checking whether a clob variable is NULL in a database trigger, which fires when a record is inserted thru the forms. The NOT NULL is working fine and updating but the NULL condition is not working, the trigger goes like this:
Create or replace trigger Tri_desc
after insert .....
declare
a_var CLOB;
b_var CLOB;
cursor c1_desc is
select desc
from tab1
where ..... = .....;
cursor c2_desc is
select desc
from tab1
where ..... = .....;
Begin
open c1_desc;
fetch c1_desc into a_var;
close c1_desc;
open c2_desc;
fetch c2_desc into b_var;
close c2_desc;
IF a_var is NULL then
update tab2
set description = b_var
where ... = ...;
elsif a_var is not null then
update tab2
set description = a_var
where ... = ...;
end if;
exception
end;
Got any idea or suggetions?
null

Answer 1

Use the alter table command and move_table_clause option. Fore more information refer Oracle SQL Reference.
The move_table_clause lets you relocate data of a nonpartitioned table into a
new segment, optionally in a different tablespace, and optionally modify any of its
storage attributes.
You can also move any LOB data segments associated with the table using the LOB_
storage_clause and varray_col_properties clause. LOB items not
specified in this clause are not moved.