I can accomplish the same task using a database function (i.e. dsum), a

math function (i.e. sumif), and an array formula. If my goal is to

make the spreadsheet run as efficiently (fast) as possible, which

should I choose? Let's assume this is a very large set of data, and if

pertinent, the equation will be used frequently.

Also, I've heard array formulas in large volumes can slow down a

spreadsheet considerably. Why is this the case? What is the best

source for finding out information like this?

Thanks for your help.

## Bookmarks