How to find foreign keys that don't have corresponding indexes?

I have installed Oracle database 11g R2 with a customized application. In my environment we are experiencing locking on tables. I want to check if there are foreign keys in my database without the corresponding indexes. Is there any query or procedure to find un-indexed foreign keys?

Oracle SQL Developer ships with a report to find these unindexed columns.

Reports to access this feature">

Here's the SQL behind this report:

```
select a.owner "Owner",
a.table_name "Table_Name",
a.constraint_name "Constraint_Name",
a.columns "Foreign_Key_Column_1",
b.columns "Foreign_Key_Column_2",
a.owner sdev_link_owner,
a.table_name sdev_link_name,
'TABLE' sdev_link_type
from
( select a.owner, substr(a.table_name,1,30) table_name,
substr(a.constraint_name,1,30) constraint_name,
max(decode(position, 1, substr(column_name,1,30),NULL)) ||
max(decode(position, 2,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 3,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 4,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 5,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 6,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 7,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 8,', '||substr(column_name,1,30),NULL)) ||
max(decode(position, 9,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,10,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,11,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,12,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,13,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,14,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,15,', '||substr(column_name,1,30),NULL)) ||
max(decode(position,16,', '||substr(column_name,1,30),NULL)) columns
from sys.dba_cons_columns a,
sys.dba_constraints b
where a.constraint_name = b.constraint_name
and a.owner = b.owner
and (:OWNER is null or instr(b.owner, upper(:OWNER))>0)
and b.constraint_type = 'R'
group by a.owner, substr(a.table_name,1,30), substr(a.constraint_name,1,30) ) a,
( select table_owner,
substr(table_name,1,30) table_name, substr(index_name,1,30) index_name,
max(decode(column_position, 1,substr(column_name,1,30),NULL)) ||
max(decode(column_position, 2,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 3,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 4,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 5,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 6,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 7,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 8,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position, 9,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,10,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,11,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,12,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,13,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,14,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,15,', '||substr(column_name,1,30),NULL)) ||
max(decode(column_position,16,', '||substr(column_name,1,30),NULL)) columns
from sys.dba_ind_columns
group by table_owner, substr(table_name,1,

StackExchange Database Administrators Q#132617, answer score: 7