Randy Clamons wrote, "Add a column to your states
table that references the ECode of the EcoRegion. That
will allow you to classify the smallest jurisdiction
to an eco-region and limit the number of rows you need
to maintain in the EcoRegions table. Create a unique
index on ECode in the EcoRegions table."
OK, let's say my states table has 50 rows, for each of
the 50 states. The primary key is either a column with
the numerals 1-50 or a column with the postal codes
(ak through wy).
Here some sample rows:
1 | Alaska | state | ak
40 | Montana | state | mt
46 | Virginia | commonwealth | va
Now suppose I add a column with EcoRegion symbols,
beginning with the Great Plains. Montana's row now
looks like this:
40 | Montana | state | mt | GP
But Montana also includes the Rocky Mountains. That
means I have to add two rows:
40 | Montana | state | mt | GP
41 | Montana | state | mt | RM
or do this:
40 | Montana | state | mt | GP,RM
Since creating two rows would presumably mess up my
primary key, am I correct in assuming I should dump
all the EcoRegion codes for a particular state in one
cell?
Also, I'll be linking to EcoRegions from my Nations
table, too:
36 | Brazil | nation | lsv (La Selva)
226 | United States | nation | GP,RM,etc.
Is this the best way to do it?
__________________________________
Do you Yahoo!?
Yahoo! Movies - Buy advance tickets for 'Shrek 2'
http://movies.yahoo.com/showtimes/movie?mid=1808405861
