limiting access to (through) views

Hi All,

I need to limit access to certain rows of a table. It was suggested to do this via a view, but it seems to me that I need the current username that is logged in to do this. Also I need to get info from another table inorder to make this work. Can I have multiple selects in a single view using the output of one in another?

Example:

table1:
col1,col2,col3

table1 Data:
test,here,max
test1,here1,me
test2,here2,one
test3,here3,max
test4,here4,one
test5,here5,two

table2:
username,key

table2 Data:
user1,max
user2,one
user3,two
user4,me

So I have these two tables, I authenticate and gain access to the db. How do I know who I am in a query? I need to query table2 for the key of the username I am. Then I need to query table1 for rows that col3 matches the key I got from the previous query.

Is this possable with a view?

Thanks

Glenn