select all vaues, including those not in row

[Larry Woods]

Here is what I want to do:

SELECT x FROM tbl WHERE x in (100,200)

where there is NO '200'


with an output:

x
----------------
100
NULL

or some variation of this, such as:

x ?
_____________________
100 | 100
200 | NULL

I just don't want to have to issue separate SELECTs for each value.

Thanks