Material_Number
'G1979-64000'
'G1979-64000    '

 create table desc_table (
 material_number varchar2(18) not null,
 description     varchar2(50),
 language_code   varchar2(2) not null,
 constraint pk_mat_lang_cd primary key (material_number,language_code))
/
insert into desc_table values('ABC', null,'EN')
/
insert into desc_table values('ABC  ',null,'EN')
/
commit
/
select * from desc_table where material_number like 'ABC%'
/

insert into desc_table values('ABC',null,'EN')
/
insert into desc_table values('ABC   ','with space','EN')
/
insert into desc_table values('123',null,'IT')
/
insert into desc_table values('123   ','with space','IT')
/
commit
/
select regexp_replace(material_number||chr(9)||'foo', '[[:space;]]',' ')material_number,
description,language_code
from desc_table
/

MATERIAL_NUMBER  DESCRIPTION  LANGUAGE_CODE  
ABCfoo                       EN             
ABC   	foo       with space   EN             
123foo                       IT             
123   	foo       with space   IT 

SCOTT@orcl_12.1.0.2.0> select rowid, material_number,
  2  	    case when material_number = trim(material_number)
  3  		 then 'without space'
  4  		 else 'with space'
  5  	    end as space
  6  from   desc_table
  7  order  by material_number
  8  /

ROWID              MATERIAL_NUMBER SPACE
------------------ --------------- -------------
AAAgZSAAGAAArJGAAC 123             without space
AAAgZSAAGAAArJGAAD 123             with space
AAAgZSAAGAAArJGAAA ABC             without space
AAAgZSAAGAAArJGAAB ABC             with space

4 rows selected.