On 08/05/2011 07:32 PM, jeffrey wrote:
I have a table that looks like this:
homeid city date measurement pre/post
123 san francisco 1/2/2003 1458 pre
123 san francisco NULL 1932 post
124 los angeles 2/4/2005 938 pre
124 NULL NULL 266 pre
124 los angeles 7/4/2006 777 post
I'd like to write a query so that I get the following result:
homeid city date measurement pre/post
123 san francisco 1/2/2003 1458 pre
123 san francisco 1/2/2003 1932 post
124 los angeles 2/4/2005 938 pre
124 los angeles 2/4/2005 266 pre
124 los angeles 7/4/2006 777 post
If a city or date is null, then it will fill from other not null
values with the same homeid. If given the choice, it will
preferentially fill from a row where homeid AND pre/post match. But
if that doesn't match, then it will still fill from the same homeid.
Does anyone have ideas for this?
Thanks,
Jeff
You need a primary key on the table to do this. Then you can do a self
join and update the correct values.
Sim
