I am trying to update values in a column (in a live table). However, this depends on the values generated from another table as well.
when I do:

select *
from Table(s) with  left outer join
where condition
I get the specified records.

However, when I try to update the column fields using
UPDATE LiveTable
SET column = 'string value'
where exists
(
--same block of select statement as above i.e.
select *
from Table(s) with left outer join
where condition
)
I get all records in the live tables (which I don't want)

I'm sorry if this sounds like a trivial problem, but I am stuck and any help is greatly appreciated.
Thanks in advance!!!