Usualy dead lock are because of unindexes foreign keys.

I have a script to find them and one to create them.

Here's a script to find them:
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column columns format a30 word_wrapped
column tablename format a15 word_wrapped
column constraint_name format a15 word_wrapped

select table_name, constraint_name,
cname1 || nvl2(cname2,','||cname2,null) ||
nvl2(cname3,','||cname3,null) || nvl2(cname4,','||cname4,null) ||
nvl2(cname5,','||cname5,null) || nvl2(cname6,','||cname6,null) ||
nvl2(cname7,','||cname7,null) || nvl2(cname8,','||cname8,null)
columns
from ( select b.table_name,
b.constraint_name,
max(decode( position, 1, column_name, null )) cname1,
max(decode( position, 2, column_name, null )) cname2,
max(decode( position, 3, column_name, null )) cname3,
max(decode( position, 4, column_name, null )) cname4,
max(decode( position, 5, column_name, null )) cname5,
max(decode( position, 6, column_name, null )) cname6,
max(decode( position, 7, column_name, null )) cname7,
max(decode( position, 8, column_name, null )) cname8,
count(*) col_cnt
from (select substr(table_name,1,30) table_name,
substr(constraint_name,1,30) constraint_name,
substr(column_name,1,30) column_name,
position
from user_cons_columns ) a,
user_constraints b
where a.constraint_name = b.constraint_name
and b.constraint_type = 'R'
group by b.table_name, b.constraint_name
) cons
where col_cnt > ALL
( select count(*)
from user_ind_columns i
where i.table_name = cons.table_name
and i.column_name in (cname1, cname2, cname3, cname4,
cname5, cname6, cname7, cname8 )
and i.column_position <= cons.col_cnt
group by i.index_name
)
/

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Here's a script to create them:

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create global temporary table temp_index
(commande varchar2(500))
on commit delete rows
/

define Tablespace_name = &&Tablespace_name

set feedback off
set linesize 255
set serveroutput on
set verify off
set heading off;

declare
L_nom_colo varchar2(2000);
--Cette requête retourne les contraintes référencées.
Cursor sel_cons is
Select constraint_name, table_name
from user_constraints
where constraint_type = 'R';
--Cette requête retourne le ou les colonne(s) de la contrainte.
Cursor sel_colo(P_nom_cons user_cons_columns.constraint_name%type,
P_nom_tabl user_cons_columns.table_name%type) is
Select column_name
from user_cons_columns
where constraint_name = P_nom_cons
and table_name = P_nom_tabl
order by position;
--
begin
--
for liste_cons in sel_cons loop
L_nom_colo := null;
for liste_colo in sel_colo(liste_cons.constraint_name, liste_cons.table_name) loop
if L_nom_colo is not null and liste_colo.column_name is not null then
L_nom_colo := L_nom_colo || ',';
end if;
L_nom_colo := L_nom_colo || liste_colo.column_name;
End loop;
--
insert into temp_index values('Create index ' || liste_cons.constraint_name || ' on '
|| liste_cons.table_name || '(' || L_nom_colo || ') tablespace &Tablespace_name;');
end loop;
end;
/

spool &SCRIPT_NAME

select * from temp_index;

spool off

drop table temp_index;
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