begin
for cur in (select fk.owner, fk.constraint_name , fk.table_name
from all_constraints fk, all_constraints pk
where fk.CONSTRAINT_TYPE = 'R' and
pk.owner = '&which_owner' and
fk.R_CONSTRAINT_NAME = pk.CONSTRAINT_NAME
and pk.TABLE_NAME = '&which_table'
) loop
execute immediate 'ALTER TABLE '||cur.owner||'.'||cur.table_name||
' MODIFY CONSTRAINT '||cur.constraint_name||' DISABLE';
end loop;
end;



select * from dba_extents
where file_id = &file_id
and &block_id between block_id and block_id + blocks - 1;