Update Query Date Subtract

[Ciprian]

I'm trying to update column 2 based on column 1, by subtracting 1 month.

exaple:

Column1 -----> Column2
01-09-2011 01-08-2011
02-09-2011 02-08-2011
01-10-2011 01-09-2011

So any idea how to write the Update Query ?

 

[boblarson]

This is data that should not be stored (violation of rules of normalization and potentially a source of incorrect data - referential integrity). It should be in a select query that is used instead of the table directly when the value is needed.