query help

Here is a simplified example of what I need to accomplish.

I have a table that keeps track of plastic balls in tubs. Based on a bit column the record is either defining balls added to a tub or taken away. When the record is defined as adding balls to a tub it will say how many and what color, but when the flag says they have been taken away from a tub I only know the number removed and not the color.

There are multiple tubs and multiple colors. So say tub1 has 20 balls in it (50% red, %25 green, and %25 blue). Also say tub2 has 10 balls in it (100% red). This is our starting point.

Now on day one, 5 balls from tub two are put into tub one. So we know that 5 balls of 100% red are put into tub one. This means that tub one now has 25 balls in it. By doing some weighted percentages, tub one now has these percentages: red = 60%, green = 20%, and blue = 20%.

Say on day two however, 5 balls are removed from tub one and placed back into tub two. We cannot say anything about the colors, but that they are: .6red, .2green, and .2 blue. So if we want a percentage for tub two on day 2 we now get: .8red, .1green and .1blue.

The math for the new percentage is I believe = ((originalPercent * originalCount) + (addedPercent * addedAmount)) / newTotalBallCount

I need a query that will give me the percentages of the different colors in the tub for any given day. This is really a running percentage that has to take every transaction into account.

This is a complicated query fro me to figure out, but can someone point me in the right direction?

LLeuthard wrote:

Say on day two however, 5 balls are removed from tub one and placed back into tub two. We cannot say anything about the colors, but that they are: .6red, .2green, and .2 blue. So if we want a percentage for tub two on day 2 we now get: .8red, .1green and .1blue.

too superfluous.

is this thing about permutation and combination/? how did u say taht 6r,2g,2b?

|||Are you saying it is not worth my time or that it is impossible? Is there a stored proc I could write that would do this easily?|||

I got .6Red .2Blue and .2Green by saying that:

5 balls of 100% red were moved to tub1. so tub1 originally has a estimate of .5*20 = 10Red balls.

Take the estimate of 10Red and add the estimate of 5Red and we get an estimate of 15Red out of 25 in tub1. This makes for .6Red at the end of day 1.

Do the same with the others.