SQL How to populate a NULL value -

here scenario:

i have table fields:

policyid membertype  memberaddress membercity 

there 2 membertype classifications:

membertype ---------- owners   dependents 

only owners linked address , city. when have owner , several family members (dependents) owners row shows address, dependents row address field shows null (side note: owner , dependent of same family have same policyid). how can populate address field when there dependent null address field grab address of owner , populate field.

current results

policyid    membertype  memberaddress    membercity  --------------------------------------------------  1234       owner       9785 sw 197 ct   miami   1234       dependent   null             null   1234       spouse      null             null  

desired results

policyid    membertype  memberaddress     membercity ----------------------------------------------------  1234        owner       9785 sw 197 ct    miami  1234        dependent   9785 sw 197 ct    miami  1234        spouse      9785 sw 197 ct    miami  

thank in advance!

update t set t.memberaddress = t2.memberaddress , t.membercity=t2.membercity table1 t  inner join table1 t2 on t.id = t2.id  t2.policyid = t.policyid , t.membertype<>'owner' , t.memberaddress null 

before running update check ensure updating correct data:

select t.policyid, t2.policyid, t.membertype, t2.membertype, t.memberaddress, t2.memberaddress, t.membercity, t2.membercity table1 t  inner join table1 t2 on t.id = t2.id  t2.policyid = t.policyid , t.membertype='dependents' , t.memberaddress null