[postgis-users] changing a non spatial table to a spatial talble

[Kirk R. Wythers]

I am new to postgis. I am running GRASS GIS with a a postgresql  
attribute table which contains x,y coordinates and point data. I  
would like to see if I could get this table spatially indexed. I have  
postgis installed, but no geometry columns inserted yet.

Can I alter a column that holds at UTM coordinate from double  
precision to geometry, or should I add a new spatial columns for the  
x and y's and then copy them into the new column?

This is one of those, "I want to change a non spatial table to a  
spatial table" questions? Can I alter this table in any way, or  
should I start over?

Thanks,

Kirk