Unique constrant

Question

oracle database 10G.
I have created one table T_BOP with unique constraint I_BOP_UK, subsequently I have dropped the constraint and it is not showing in user_constraints also
but when I trying to insert row in above table it is showing above constraint I_BOP_UK.
Any reason?

Answer 1

A unique constraint is supported by a unique index but as you said you have dropped the constraint so the index should have been dropped with it.
SQL> create table tt (id number, constraint tt_uk unique (id));
Table created.
SQL> select constraint_name from user_constraints where constraint_type='U';
CONSTRAINT_NAME
TT_UK
SQL> select index_name from user_indexes where index_name like 'TT%';
INDEX_NAME
TT_UK
SQL> alter table tt drop constraint tt_uk;
Table altered.
SQL> select constraint_name from user_constraints where constraint_type='U';
no rows selected
SQL> select index_name from user_indexes where index_name like 'TT%';
no rows selected
SQL> insert into tt values (1);
1 row created.
SQL> insert into tt values (1);
1 row created.
SQL> insert into tt values (1);
1 row created.
SQL> select * from tt;
        ID
         1
         1
         1 Can you please post here how did you create the constraint and then dropped it?