Correct update statement

Hi

Please help, we are using postgreSQL 9.2.4. I need to update over 9000
rows. See the query below: A table called contact has got *addr_id *field
as null which is incorrect. So now I need to update contact table for each
account (cus_acno is in cus table) where contact_addr_id is null. For
example using the first of the results below: I need take set addr_id (in
contact table) to 187479 where cus_acno = 243492 and con_id = 119360

Example:

select distinct(cus_acno), contact.con_id, address.addr_id from address
join person using (addr_id) join cus using (per_id) join link_contact
using (cus_acno) join contact using (con_id) where contact.addr_id is null;
cus_acno | con_id | addr_id
----------+--------+---------
243492 | 119360 | 187479
393701 | 119824 | 458532
388538 | 118413 | 453178

Thanks

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