How to optimise update query

Question

Hi,
If following query, i tried to check the  plan i noticed both where same
pls suggest as thum of rule what should be followed.
thought i will check plans in each cases.
1)
update t1 
set a, b, c, d .f
from t1 a
join t2 b on a.t1id=b.t1id
where b.poleid =1
2)
update t1 
set a, b, c, d .f
from t1 a
join t2 b on a.t1id=b.t1id
where a.poleid =1
--t2 keeps poles and poleid is pk
--t1 keeps poles report and does not have any index right now, we are planning for (includes)
it is 2 times bigger than t1 
q1) which where clasue i should select
q2) should i revers the join by putting t2 first and t1 second.
yours sincerely

Answer 1

Sorry copy past problem please consider following
Q1)
1)
update t1 
set a
= b.a, bc = b.bc, c=b.c, d=b.d
from t1 a
join t2 b on a.poleid =b.poleid 
where b.poleid =1
2)
update t1 
set a
= b.a, bc = b.bc, c=b.c, d=b.d
from t1 a
join t2 b on a.poleid =b.poleid 
where a.poleid =1
Q2) Will b.poleid = 1 will perform better in all conditions because it is pk of t2 or both queries will perform same.
Q3) Can i write like following, that is , can t1 which i want to update, be the second table in from clause.
update t1 
set a
= a.a, bc = a.bc, c=a.c, d=a.d
from t2 a
join t1 b on a.poleid =b.poleid 
where a.poleid =1
yours sincerely