Counter change

[ready4data]

I have a table with RowId(autonumber),ReportMonth(date), SerialNumber(text), and Counter(number)

I'm trying to create a query that will eventually be a Make table query.

I want to show for each ReportMonth and each SerialNumber, the increase or decrease of the Counter.

Issue is that there might not be a SerialNumber and Counter every ReportMonth. Sometimes they may skip a month or a brand new SerialNumber may be entered so that record should show the current Counter.

I'm looking for ideas how to accomplish this,
Scott

 

[KenHigg]

Using an autonumber in this manner is not recommended. Counted stuff is usually possible using other means...

 

[Frothingslosh]

Step back a bit. What is the purpose of this counter? Are you just attempting to keep a count of records added over a given time? That kind of thing can easily be done in your queries without storing a contrived value like a counter.

 

[ready4data]

The Counter(number) field may have been a poor choice of name. It contains a monthly meter reading.
I used RowId(autonumber) because that was required in some Running Sum queries I was trying. It didn't work correctly as there isn't a meter reading every month for some serial numbers.

Scott

 

[KenHigg]

How many records total would you need to go through in one run of the query? You could create a function to do it...

 

[spikepl]

I'm with Frothingslosh on this one. You've started of with some techno-stuff, which is your intended solution to a problem which we still do not know what is, and is diffiuclt to deduce exactly from the tidbits supplied.

Back up, forget database, and explain in plain language what this is about.