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create table owner (owner_name varchar(10), ref_no varchar(10));
insert into owner values ('Ajmal', '48534'), ('Jeewan', '42'), ('Samal', '5534'), ('Jeewan', '42');
4 rows affected
SELECT owner_name
, ref_no
, LEFT(ref_no + '########', 8) updated_ref_no
FROM owner;
| owner_name | ref_no | updated_ref_no |
|---|---|---|
| Ajmal | 48534 | 48534### |
| Jeewan | 42 | 42###### |
| Samal | 5534 | 5534#### |
| Jeewan | 42 | 42###### |