Finding FK for a Parent table

select owner,constraint_name,constraint_type,table_name,r_owner,r_constraint_name

     from all_constraints

    where constraint_type='R'

    and r_constraint_name in (select constraint_name from all_constraints

    where constraint_type in ('P','U') and table_name='T_LOOKUP');

select 'alter table '||a.owner||'.'||a.table_name||

            ' disable constraint '||a.constraint_name||';'

            from all_constraints a, all_constraints b

            where a.constraint_type = 'R'

            and a.r_constraint_name = b.constraint_name

            and a.r_owner  = b.owner

            and b.table_name = 'T_LOOKUP';