I am looking for advice on how to complete an action in the context of an
My database stores financial information for customers on a year-to-year
basis. Each customer has a unique id, and when combined with the calendar
year, unique keys are formed for all the data, which can then be used to
easily retrieve date either by (i) customer, all years or (ii) by specific
year, all customers.
At the completion of each year, a new row of data is appended for every
customer. Most of the data is completely new, and is easy to add. But there
are two elements I want to add which releate to the previous year, which I
cannot figure out how to do....yet. ;-)
1) I want to take a value from the previous year for each customer, and add
it to this year's record in another location. The values in question are
Ending Value and Beginning Value..that is, last year's End Value for every
customer becomes this year's Beginning Value.
2) The second need is very similar. This time, I want to update a Running
Total value...it is the sum of last year's Running Total plus a new value
from this year.
I am trying to figure out how I can use the unique customer id and the year
to identfy the records I need in order to complete the operation...but no
luck so far. Any help would be appreciated.