Concatenating Fields

I'm looking for ideas / options for concatenating several fields into one based on a sequence number. The sequence could go as high as 90 but I'm only interested in concatenating the first 3 sequences. I'd like to compare when seq is the same as the id, it's concatenated and placed in a virtual column.



Example:

table x:
column:attritbute
id:123
fname:xyz
lname:zmith
seq:1
address: 123 something
id:123
fname:abc
lname:zmith
address: 123 something
seq:2

Query:
select *
from x
where id = 123

would return 2 records:

ID | Concat | address | fname | lname
123 | abc / xyz | 123 something | xyz | zmith
...

I would like it to return:
ID Concat address
123 | abc / xyz | 123 something ....

Thanks!